Jesus’ faith generates life to live by, and nothing less.
Notice that phrase, ‘I live by the faith of the Son of God.’ Let’s dig into this. Look closer. Let’s get hold of ‘the faith of the Son of God.’ You may notice that nearly all modern translations of the Bible say, ‘I live by faith in the Son of God.’ Here lies a very important preposition battle, which deserves our careful and humble evaluation: do we understand this as ‘the faith in’ or ‘the faith of’ the Son of God, that Paul lived by?
The following is a respectful challenge. Here’s why we cannot translate Gal. 2:20 as ‘I live by faith in the Son of God.’ Our Greek Text (United Bible Societies, Third Edition, edited by Kurt Aland, etc., printed in the Federal Republic of Germany, 1966; p. 653) has: ἐν πίστει ζῶ τῆ τοῦ υὶοῦ τοῦ θεοῦ.To the trustiest (not really debatable) Greek Grammar we now turn: A Manual Grammar of the Greek New Testament by H. E. Dana and Julius R. Mantey (The Macmillan Company, 1927, 1955, printed in the United States of America). This could get a little technical, but hang in there. You’re examining Greek grammar now and you got this.
The Position of the Article
The first question is: how do we understand the position of the article in our phrase, ‘by the faith of the Son of God’? In Greek the article is τῆ. ‘By the’ is in bold print above and is the article. Without this article we would simply have ‘by faith of the Son’ and it would merely be a general statement about faith. But the article ‘by the’ is there and its position is critical. The word ‘faith’ is in the predicate position in grammar because of the location of the article. That is, the article ‘by the’ comes after the word ‘faith’. This seems awkward to the English ear, but the article’s position is yelling to us in Greek, Hey, look at me! ‘I live by faith; wait a second, by ‘the’ faith of the Son of God. The article commands weightiness as it does not come immediately before its noun ‘faith’, but after.
So since the article ‘by the (faith)’ comes after the noun ‘faith’, Dana and Mantey say, “A noun (‘faith’) never takes an article in this predicate position unless there is some very special reason for it.” That ‘very special reason’ is: this faith belongs to the very Son of God. They continue, “When the article is used with the predicate (‘by the faith’) it marks its essential identity with the subject (‘of the Son of God’)” (p.152). It lends greater emphasis and prominence to the clause it defines (cf. p. 148).
One more thing: it is a rule of Greek grammar that an article must match the noun it modifies by gender and number, and this makes the noun definite, like ‘by the faith of the Son’ and nobody else. The article can only identify with the noun it modifies, ‘faith.’ It cannot connect with any other word. Got it? Ok, so here’s our translation so far: ‘I live by the faith . . . of the Son of God.’ On to the last part.
The Genitive Case with Nouns of Action
Consider now the last part of our phrase from Gal. 2:20 – ‘I live by the faith of the Son of God.’ Notice that every word of this clause in the Greek Text is in the genitive case, the case of definition or description. It qualifies the meaning and sets essential limits to the nouns that carry its force. Its root meaning is attribution. (cf. p. 72-74). Though the genitive case is most often translated as ‘of’, there are at least eight shades of meaning to consider. But the only way to get ‘faith in the Son’ and not ‘of’ with a genitive is if we conclude it as an adverbial genitive of time or of place, which isn’t the case (cf. p.77-78).
One of these eight genitive types is called ‘The Genitive with Nouns of Action.’ There are just two choices. When the genitive is constructed with nouns of action, the verbal idea will point either to the object (i.e. receiver of the action) or to the subject (i.e. producer of the action). For example, see the genitive in “The blasphemy of the Spirit” in Matt 12:31. ‘Spirit’ is a noun of action. So ‘of the Spirit’ is an objective genitive because the Holy Spirit receives the action of blasphemy, and is therefore the object of, the receiver of, the verbal idea.
On the other hand, look at the genitive in “The love of Christ” in II Cor. 5:14. ‘Christ’ is a noun of action, and so ‘of Christ’ is a subjective genitive because he manifestly produces the action of love, and is therefore the subject of, the producer of, the verbal idea (cf. p. 78-79). The reader must distinguish which genitive it is.
So, what kind of genitive do we have in our phrase, ‘I live by the faith of the Son of God’? Notice first that the ‘Son’ is a noun of action. ‘Son of God’ is in the genitive. It isn’t an objective genitive because the ‘Son’ is not receiving the action of faith (as its object). Therefore, let’s call this a subjective genitive because the ‘Son’ is producing the action of faith (as its subject). Our translation is: “I live by the faith of the Son of God.” Interesting: this is the same translation as the KJV written over 400 years ago.
Conclusions
1 The Son of God generates the faith that I live by. It does not originate in my faith but his.
2 The Bible does not say I live by faith in the Son of God, nor is that justified by the Greek Text.
3 If this is about ‘my faith in the Son of God’ then is this my faith apart from him? ‘In’ does not equal ‘of.’
4 My faith always gets inspired first by his faith. Then it becomes my faith. (Cf. Mark 10:52).
5 Our findings about the subjective genitive here will also transfer over to our understanding of:
Gal. 2:16 – “Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not the works of the law: for by the works of the law shall no flesh be justified.” Twice spoken in one verse, a man is justified ‘by the faith of Jesus Christ,’ who inspires the faith of the one hearing the Gospel.
Phil. 3:9 – “And be found in him, not have a righteousness of mine own, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith.” The ‘out-of-God righteousness’ is by ‘the faith of Jesus Christ,’ brought to you by the Father and the Son.
Eph. 3:12 – “In whom we have boldness and access with confidence by the faith of him.” In Christ we have boldness and right of access to God generated ‘by the faith of Christ.’
Rom. 3:22 – “Even the righteousness of God which is by faith of Jesus Christ unto all and upon all that believe.” Our ‘righteousness which God empowers’ is by ‘the faith which Jesus empowers.’
Rom. 3:26 – “To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.” Jesus is the source and power of both our righteousness and our faith.
Acts 3:16 – “And his name through faith in his name hath made this man strong, whom ye see and know: yea, the faith which is by him hath given him this perfect soundness in the presence of you all.” Healing came by ‘the faith which is produced by Him’, i.e. ‘by the faith generated by his name.’
Mark 11:22 – “And Jesus answering saith unto them, Have faith in God.” Jesus said, ‘Have the faith of God’ (not ‘in God’), i.e. the faith that God empowers.
Gen. 15:6 – “And he believed in the Lord; and he counted it to him for righteousness.” Abraham was inspired to believe God, or וְהֶאֱמִןIt is like the subjective genitive God-empowered faith of the NT.
Prov. 14:27 – “The fear of the Lord is a fountain of life, to depart from the snares of death.” ‘The fear of the Lord (the fear which the Lord stirs) is a fountain of life (a spring produced by life), to depart from the snares of death (the snares that death invented). This is the subjective genitive of the OT.
Application: How to Get the Faith of the Son of God
1. Realize that you were crucified with Him. Sense his nail prints in your hands.
So, you’re dead with Jesus. And you are not capable of coming alive unless the resurrected Christ is living in you. But since Christ is living in you, you live, and experience a life powered by his faith.
By now you may have figured out that there has got to be something better than just living for yourself. Right on! But if you consider yourself a good person, and if you’re not certain about your own darkness, read Romans 3. Or if you think that you can repair all collateral damage you’ve imposed on others, and improve things by putting yourself into your own personal purgatory, a little voice is telling you that it won’t work, and there’s no foundation to it, because in the end it’s still all about you. There’s your problem: you.
The solution: Reckon that it’s really a done deal: you really were crucified with Christ. The Bible really gets down to the nitty-gritty. So, you can’t crucify yourself; however, you can enter into his death. This is part of what to means to believe in Jesus. If you make yourself the judge of your life, chances are you’ll condemn yourself. But Jesus is a Judge who really wants your life, to the point that he pursued you to death. What! You don’t want his Cross now that you know about it? If you reject his Cross as your own, then you are not worthy of him (Matt. 10:38). And that means that the judgment bullet is speeding your way with your name on it. In any case, Jesus has already positioned himself right in that line of fire for you. Just to feel the hope of that, the freshness of it, is evidence that his faith is already acting upon you.
When Jesus invites you into his Cross, that is the most relational, hyper-personal unity you could ever get from anybody. If you believe that, you’re tight with God. This is faith: refusing self-justification by the law of God, you die to the law by joining Jesus in his death for you. That is the faith of the Son of God at work in you. But the Lord also said, “For whosoever will save his life shall lose it; but whosoever shall lose his life for my sake and the gospel’s, the same shall save it” (Mark 8:35). The effects of being crucified with him will pass into the future, into eternity, forever forging a bond with Jesus of friendship and destiny. It is salvation by faith, a faith that Jesus inspires. Feel the bond; tremble.
2. Live by the Faith of the Son of God, who loved you and gave himself for you.
This relational bond with Jesus isn’t about ‘once and done.’ It’s about a life time of dependence on his faith at work in you. If not, that would be to say to the Lord, I got this now. However you look at it, faith is a gift: there is the ‘fruit of the Spirit’ called faith (Gal. 5:22), and there is the ‘gift of the Spirit’ called faith (I Cor. 12:9). Notice that the Holy Spirit is the giver, and these are never the result of human striving: “for by grace are ye saved through faith; and that not of yourselves: it is the gift of God: not of works, lest any man should boast” (Eph. 2:8-9). We don’t arrive at faith without him.
Remember the mustard seed: so tiny, but once planted you could never find it again; yet so mighty, it could move a mountain (Matt. 17:20). Faith has to be of God to achieve that. But it becomes your faith, too. His Cross is your cross, his life is your life, and his faith is your faith. You are involved. Own it, live it. It comes into everything, as Matthew would say, even walking on water (Matt. 14:22-33).
Consider Paul’s view of the Cross: Jesus, while representing the world to God as condemned, was also representing Paul personally and individually. By virtue of this, Paul also saw himself personally and individually with Jesus on the Cross, so that he shared in it, saying: ‘I have been crucified with Christ,’ lit. ‘Crucified in Christ.’ He is dead to sin, dead to the law, and dead to the world. Yet he lives, but no – it’s Paul’s substitute, Christ, ‘who lives in me, the one who loved me and gave his life for me.’
Finally, to be crucified with him, makes you capable to ‘live by the faith of the Son of God.’ This is what you were wired for, and why you’re alive. The faith Christ is generating in you is not some knock-off brand of faith; it’s the exact re-production of the original, the genuine article, his very own faith. And his faith corresponds to your uniqueness perfectly. It swings you into his ancient destiny chosen for you, ‘before the foundation of the world’ (Eph. 1:4). Think of the continuity that gives you with eternity. His faith working in you is that one mysterious ‘missing piece’ you’ve been longing for, beyond longing. But like the Kingdom of God in the Parable of the Hidden Treasure of Matt. 13:44, it will cost you not less than everything you’ve got to ‘buy’ it, and a steal at that. It is merely the faith of our Lord, Jesus Christ.

Tim Halverson