Gospel Guidebook: Getting and Keeping It Right 
Justification and the Gospel of John
It might seems strange to speak about "justification" in the context of the Gospel of John, since John never uses the word "justification" in the context of declaring a sinner righteous. However, I believe the concept of justification is there, if we read between the lines. The Gospel of John is the only book in the Bible that was written a purpose statement of teaching people how to receive eternal life. In John 20:31 we read, "But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name." Is it possible to talk about eternal life without also talking about justification? I don't think so. The Apostle Paul talks about the gift of righteousness (Romans 5:17), but he also talks about the gift of eternal life (Romans 6:23). In fact, almost immediately after telling us that righteousness is a gift, he tells us that "grace reign[s] through righteousness unto eternal life" (Romans 5:21). Reading the context of Romans 5:12-21, it is clear that this righteousness is not our own ethical righteousness. Rather, it is the gift of righteousness given to us on account of the Obedient one who makes us righteous (or "constitutes us righteous") (see Romans 5:19 YLT). So, what we have is grace reigning through righteousness unto eternal life (Romans 5:21). This seems to imply that justification precedes regeneration. At the same time, in Romans, we learn that we are justified by believing in Jesus Christ. Similarly, in John, we learn that we receiving eternal life by believing in Jesus Christ. So, we see that there is a close relationship between "believing," "justification," and "eternal life."
In light of the above, even though justification of the sinner is not directly mentioned in the Gospel of John, I do believe it is there if we read between the lines. For instance, let's consider John 1:12, "But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:" Here we learn that people who believe in Jesus' name receive power to become the sons of God. John is saying that "believing" precedes "being given power," and "being given power" precedes "becoming a son of God." The Greek word translated "power" can also be translated as "authority" or "right." I think this "giving of authority" may refer to what Protestant's call forensic justification (i.e., that we are declared righteous on account of being given an extrinsic righteousness solely on the basis of what Christ did for us), and it is because of this "authority" that we become sons of God.
Another example where we can read between the lines in the Gospel of John is John 3:32-36. In John 3:32-33 we read, "32 And what he hath seen and heard, that he testifieth; and no man receiveth his testimony. 33 He that hath received his testimony hath set to his seal that God is true." If we compare these verses with John 3:11-12 in consideration of the immediate context of "believing" to receive eternal life (John 3:36), we can deduce that "receiving testimony" is equivalent to "believing." John the Baptist is telling us that when we receive his testimony as being true, we are really setting our seal that God is true. To set a seal often has legal significance, and this reminds us of Paul's discussion of Abraham in Romans 4 where he speaks in legal terms of being imputed with righteousness and tells us how Abraham was "fully persuaded that, what he had promised, he was able also to perform" (Romans 4:21). In other words, Abraham received God's testimony as being true. He was fully persuaded by it. And it was this kind of faith that represented the faith he had when he believed in God and it was imputed to him for righteousness (Romans 4:22). John the Baptist speaks in similar terms, but here the setting of one's seal of God's truth results in eternal life (John 3:36). So, I think "setting one's seal that God is true" may refer to the moment of "forensic justification."
I think another example may be in John 3:17-18 and John 5:24 where Jesus speaks of not being condemned and not coming into judgment. In Johh 5:24 (NASB) He says, "Truly, truly, I say to you, he who hears My word, and believes Him who sent Me, has eternal life, and does not come into judgment, but has passed out of death into life. " In this verse, we see that "believing Him who sent Jesus" results in "eternal life" and "not coming into judgment." Not coming into judgment (or condemnation in the context of John 3:17-18) is essentially one aspect of justification.
It is interesting that "not coming into judgment" is supplemented by the phrase "but has passed out of death into life." Obviously, a person needs to "pass out of death into life" before he can have "eternal life." The word "but" (Gr. alla) is an emphatic contrastive conjunction, so I wonder if the nuance of this verse is something like, "does not come into judgment, but [instead] has passed out of death into life." This would imply that something took place to change the person's legal status from being under condemnation (John 3:18) to being justified, resulting in the ontological transformation of "passing out of death into life." On the other hand, this verse might simply be telling us that "not coming into judgment" is characteristic of people who "have passed out of death into life" and obtained "eternal life." I don't think it can be used to teach that "not coming into judgment" is the direct result of "having passed from death into life" because of the contrastive conjunction alla (but). If Jesus wanted to (explicitly) teach that "not coming into judgment" is the result of "having passed from death into life," then He could have easily used a conjunction such as hina (so that, in order that) to signify purpose or a conjunction such as dia (because) to signify causation. Overall, John 5:24 is too vague to draw any solid conclusions, but it does hint that there is a reversal of legal status from being condemned to being justified.
Pisteuo (to believe) and its relation to eternal life and justification
It is also interesting that the Greek verb pisteuo (to believe) appears nearly 100 times in the Gospel of John. In contrast the Greek noun pistis (faith/faithfulness) does not appear a single time. Similarly interesting, the Greek verb and noun that represent "to repent" and "repentance" do not appear even a single time in the Gospel of John. John really emphasizes that it is the simple moment of "believing" in Jesus that results in eternal life. And as mentioned above, the Gospel of John is the only book in the Bible that has a purpose statement of teaching people how to receive life. It is an evangelistic book. This should not be ignored when we read the Letter to the Romans. In contrast to the Gospel of John, Romans was written to people who were already believers. Therefore, Romans really needs to be read in the context of the Gospel of John. In this respect, I believe that when Paul uses the word pistis (faith/faithfulness) in Romans, he is usually speaking of an "objective faith" (i.e., a faith that has an object), such as "faith in Jesus," in harmony with Jesus' own teaching in the Gospel of John that "whoever believes in me has eternal life" (John 6:47 KJV, etc.).
With this backdrop, I think it is important to carefully examine the meaning of "believing in Jesus," because it is by "believing in Jesus" that we are justified and receive eternal life. To do this, let's take a look at John 3:14-15 and then move into John 3:16-21, since these are probably the most famous (if not the most important) words in the whole Bible. In John 3:14, Jesus provides us the backdrop behind his promise of "believing in him for eternal life." This backdrop brings us back to the Old Testament book of Numbers.
Numbers 21:5-9
In Numbers 21:5-9, we learn that the Lord sent venomous snakes among the people due to their complaining. As a result, the people expressed instant regret because of the consequence of their sin and pleaded with Moses to pray to the Lord to take away the snakes. The Lord in His mercy provided them with a simple solution. He commanded Moses to create a bronze snake and put it on a pole so that the people who were bitten could be saved (i.e., retain their life) when they looked at it. Apparently, all it took was one look at the bronze snake to be saved.
A careful reading of Numbers 21:5-9 will show that God did not take away the venomous snakes from among the people. If the people had really repented and shown remorse for the cause of their sin, then it is likely that God would have taken away the snakes from them and healed their land. As mentioned in the previous paragraph, this implies that the people's confession of sin in verse 7 was only because they regretted the consequence of their sin. In other words, they regretted being bitten. They wanted to be delivered from their suffering. It was really a selfish motivation, but God in His mercy took heed to them, knowing their weaknesses, and provided them with a simple solution. In verses 8-9, we see that the snakes did remain among the people, but now, instead of dying from the venom, whoever was bitten could simply look at the bronze snake on the pole and be saved. I suspect that the people were finally delivered from the venomous snakes when they moved toward Oboth and beyond (see verses 10 ff.). However, as we know from the story of Israel in the Old Testament, they were never able to master their sinful nature and were plagued by various types of "snakes" throughout their history.
Given the information we know, we can't assume that everyone who was saved from their snake bite never complained again throughout their life. But it is important to recognize that looking at the bronze snake was never conditioned upon the need to stop complaining. In other words, it was not indicative of moral reform. The fear of being bit probably created a good amount of moral reform in Israel, but for those who sinned (or continued to sin), their healing was not conditioned on anything. It was an unconditional salvation. Looking at the bronze snake was their vindication (i.e., justification) from the penalty of their sin.
John 3:14-21
Now, our world doesn't have a bronze snake that can save us from our temporal sufferings, but it has something much better. God in His mercy has provided the world with a better solution that is able to save us from our eternal sufferings. In John 3:14-15, Jesus likens looking at the bronze snake on the pole to believing in Him for eternal life. We learn that whoever believes in Him will not perish, but will have eternal life.
Let's look at the relevant verses. 14 And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up: 15 That whosoever believeth in him should not perish, but have eternal life.
Most people who believe in Jesus for eternal life realized that they needed a solution to the consequences of their sins, and they took Jesus at His word and just looked upon Him, just as the Israelites looked up the bronze snake. They were justified. They were vindicated. They took Jesus and His word and found what they were looking for. And Jesus is pleased to receive all such people who with child-like faith come to Him for life.
At the same time, however, there are a larger number of people among those who call themselves Christians who don't seem pleased with this easy solution to their consequences of our sins. Instead of embracing the promise of Jesus, they have created ways to obscure the simplicity of the promise in John 3:15. They don't like the idea of ungodly people receiving eternal life as ungodly people who just want a way of escape from "perishing."
The first thing these people (hereinafter, referred to as "our opponents") do is try to explain that the Greek word pisteuo translated "believe" does not mean "mental consent." They usually say that it implies trust, faithfulness, and commitment. However, this is not true. The proof of this is in John 3:11-12, just three verses before John 3:15. In those verses we read, "11 Verily, verily, I say unto thee, We speak that we do know, and testify that we have seen; and ye receive not our witness. 12 If I have told you earthly things, and ye believe not, how shall ye believe, if I tell you of heavenly things? In these verses, we can see that Jesus is equating "receiving witness" with "believing." In other words, believing means to receive witness as being true. In addition to Jesus' explanation of "believing" in John 3:11-12, John the Baptist and the Apostle John explain the same thing in John 3:32-36 and 1 John 5:9-11. All three of these verses are in the context of receiving eternal life. According to these three witnesses, "believing" indeed refers to mental consent. In John 3:15, when Jesus says, "believeth on him", he means "accepting or receiving him as being truthful." In other words, when we accept or receive Jesus as being a truthful person as pertains to His promise to us, then we know for certain that He has given us eternal life.
Despite the clear teaching of John 3:11-12, John 3:32-36, and 1 John 5:9-11, our opponents will insist that this cannot be. They'll probably say that pisteuo eis (the verb "believe" + the preposition "in"/"on") has a different meaning from the bare verb pisteuo (believe) followed by a noun in the dative case. In other words, they'll say that "believe in Jesus" is different from "believe Jesus." They'll say that the former has a special meaning that includes faithfulness and commitment. However, this is not true. I wrote an article called Belief or Trust? that shows that the expressions "believe in Jesus" and "believe Jesus" mean the exact same thing. In fact, Rudolf Bultmann came to a similar conclusion on page 203 of Volume 6 of the Theological Dictionary of the New Testament.
After this, our opponents will probably respond by saying that pisteuo (believe) is really an articular present participle ho pisteuon ("the one believing" or "he who believes"). They'll say that the Greek present tense always refers to ongoing durative action, so the meaning of "believe" in John 3:15 must refer to an ongoing life-long faith. In other words, they'll insist that "believing" does not refer to a single moment, but rather to a lifelong process and experience. However, they are wrong again. The Greek articular present participle is often used as a substantive, i.e., as a noun. As a substantive in John 3:15, it essentially means "the believer." Furthermore, it is qualified by the adjective pas (everyone), which means it is referring to a general truth statement. According to Greek grammar textbooks, this type of present tense is called the gnomic present. This is significant because the articular present participle in John 3:15 cannot be both gnomic and durative at the same time. Those two categories don't mix well. If we conflate them, we'll commit the exegetical fallacy called illegitimate totality transfer. However, in the case of John 3:15, the adjective pas provides strong evidence that we are dealing with a gnomic present participle meaning "whoever believes," "everyone who believes," or "every believer." I provide more detail on this in my article The Significance of John 3:18 as Proof of the Free Grace Position. In that article, I show very carefully that Jesus is referring to a single moment of "believing," not life-long "believing." In addition, it is a big misconception to tell people that the present tense of pisteuo (believe) refers to ongoing durative belief with the implication of lasting one's whole life. Ongoing belief can be as short as two seconds. One...two. In fact, Herbert Weir Smyth, author of the gold standard of Greek grammars, says in Section 1852 of his Greek Grammar for Colleges, "Continued action is incomplete: hence nothing is stated as to the conclusion. Thus φεύγει he flees does not state whether or not the subject succeeded in escaping." Just because a verb is in the present tense doesn't imply that an action "continues forever" or "achieves its goal." For more information on this, see my article Misunderstandings about the Greek Present Tense. Moreover, I don't even think it is correct to think of the verb "believe" as an action verb. It is a stative verb, meaning that it is not an ongoing process that keeps getting worked out.
Despite their objections to the verb "believe" not succeeding, instead of just accepting the good news of Jesus' promise of eternal life through a child-like moment of belief, our opponents will probably just raise another objection about the word "eternal life." They'll say something like "eternal life" refers to experiencing a transformed life of holiness or living according to resurrection life. To respond, I would say that I don't doubt that it does, and I don't doubt that many (if not most) of the people who believe in Jesus for eternal life start to experience "eternal life" during this life. And for those who don't start to experience it, they'll definitely experience it in the afterlife. However, it is important to note that Jesus says, "has eternal life," not "experience eternal life." It is quite possible to have something without experiencing it. If someone puts a million dollars in my bank account, I technically "have a million dollars." This cannot be denied. However, until I start using that money, I cannot be said to be "experiencing life as a millionaire." However, more to the point, this objection is really irrelevant because Jesus is talking about the "cause" of receiving eternal life, not the "result" of actually receiving it. The "cause" of receiving eternal life is a person (usually a sinner as a sinner who has nothing to offer or promise in return) believing in Jesus for it. So what we really have (in many instances) is ungodly people receiving eternal life as ungodly people. What happens after they receive eternal life is a different discussion altogether. However, I will say this, that "eternal life" is not merely qualitative in nature, such as described in John 17:3, but also quantitative, such as in John 6:47-50 where Jesus describes one aspect of eternal life as "not dying." In other words, it really is everlasting life. Also, as mentioned above, in John 5:24, Jesus describes it in the context of "not coming into judgment." This means that "eternal life" is accompanied by the "legal declaration" of "not guilty," or what is usually referred to as "justification." So, we see that "eternal life" means more than just living a transformed life of holiness.
After this, our opponents, probably feeling frustrated and desperate, will probably quote John 3:20-21 where it says, "20 For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved. 21 But he that doeth truth cometh to the light, that his deeds may be made manifest, that they are wrought in God. They'll probably say that those who come to the light do good deeds. They'll also say that this implies moral transformation. To this objection, I will once again respond by saying that I don't doubt that many (if not most) of the people who believe in Jesus for eternal life start producing good works through moral transformation during this life. And for those who don't succeed at moral transformation, they'll definitely succeed at it in the afterlife. So, the general truth of John 3:20-21 (if it indeed refers to good deeds) can be established without injuring my position at all. But again, just as I mentioned in the previous paragraph, this objection is really irrelevant because Jesus is talking about the cause of eternal life in John 3:15, not the result of receiving it. The only thing that is important in this discussion is that ungodly people receive eternal life and are justified by believing. What happens after they believe is a different topic entirely. However, I would also just like to say that John 3:20-21 does not teach what our opponents insist it does. Look very carefully at the contrast between verse 20 and verse 21. In verse 20, Jesus says "does evil." In verse 21, we would have expected Him to say, "does good," but He doesn't say this. Instead, He says, "does truth." Doing truth and doing good are not the same thing. So, when verse 21 says, "his deeds may be made manifest, that they are worked in God," it is not referring to good deeds. Instead it is referring to "truth deeds." In 1 John 1:6, the Apostle John basically equates "doing truth" with "not lying." And this is really the heart of the matter. When a sinner believes in Jesus for eternal life as a sinner, he is really telling the truth about himself and God. He knows that he has nothing to offer God. He knows that he can't make any promises of reform. But he comes as he is, as a sinner, and just believes Jesus because he judges Him as being truthful. This is really what "doing truth" is all about. John the Baptist describes "doing truth" in John 3:33 when he said, "33 He that hath received his testimony hath set to his seal that God is true." Receiving Jesus' testimony is really certifying that "God is true." There is vindication in this. This is the sinners justification. And this is the real meaning of John 3:21. In contrast, our opponents who reject the simple truth of John 3:15 are not "doing truth." They need to be careful that they do not end up hating the light and refusing to come to the light (John 3:20).
Conclusion
In this article, I have tried to show that even though the word "justification" does not appear in the Gospel of John as pertains to the "justification of sinners," there are hints of it, if we are willing to read between the lines. In addition, I have showed that similar to the "justification" taught by the Apostle Paul in Romans, "eternal life" is also received by the sinner as a sinner through a single-moment of belief. To learn more about "justification" as it is presented in Romans, I recommend my article Justification of the Ungodly Man as an Ungodly Man