This wonderful clause from Habakkuk 2:4 is quoted in three places in the epistles of Paul: Romans 1:17, Galatians 3:11 and Hebrews 10:38. In each New Testament reference an emphasis is placed upon one phrase, thus bringing into focus the matchless wonder of the grace of God and the fulfillment, though now in part, of the prophetic word.
By the grace of God Habakkuk was instructed to write of God’s response, in deliverance, to injustice done to His people by the very oppressor whom God had used to judge the people for their departure from Him. God holds all accountable for their actions. The promise here is to those who exercise faith. The immediate torment of His people requires patience but the righteous (just) must pass through this to learn to trust in God in all circumstances: he must live by faith. God has promised and He will fulfill. "Because it will surely come, it will not tarry" (Hab. 2:3).
When we arrive at the first New Testament quotation the emphasis is on the just shall live by faith. The book of Romans sets before us the Gospel of God. That God is righteous, and how, in His righteousness, He has provided through our Lord Jesus Christ and His work, a basis upon which faith may lay hold upon life. Sin and death are the part of man in this world until the salvation by faith is provided by God. Those who have been made the just who formerly were the unjust are by faith made alive Godward; they have life, through our Lord Jesus Christ.
The reference in Galatians contrasts by faith with works of law. By law men come under the curse and die, Galatians 3: 10 says, "For as many as are of the works of the law are under the curse: for it is written, Cursed is every one that continueth not in all things which are written in the book of the law to do them." All are condemned by the law and can only be justified, or cleared of every charge, by (or on the principle of) faith, and that in our Lord Jesus Christ, as He was made "a Curse for us" and bore the condemnation of a righteous and holy God. (Read Romans 8: 1-4).
The final reference in Hebrews emphasizes shall live by faith. The thought here is not that we are justified by faith, but that faith is the power for living here in this world, in anticipation of the coming of our Lord Jesus, "He that shall come will come, and will not tarry." Note the change in the pronoun from Habakkuk 2:3 from "It" to "He," as a result of the revelation of our Lord Jesus Christ, in manhood here in this world, and the promise of His coming for and with His saints. This provides a solemn warning for those who are professors of salvation but who do NOT really believe. The believer in our Lord Jesus Christ goes on to the full enjoyment of salvation, the saving of the soul, those who do not "draw back unto perdition."
Let us be those who are the just and who by faith, shall live. The promises of God are sure, it is God that justifieth (Ro. 8:33), it is God who gives faith (Eph. 2: 8), and the gift of God is eternal life (Ro. 6:23).