Scripture teaches that faith alone is the condition for salvation. A simple evidence of this is that the explicitly evangelistic gospel of John never once mentions repentance as a condition for salvation, but repeatedly exhorts us to faith (Jn. 1:12, 3:16, 6:47, 7:38, 11:25, 14:1, 20:31). Furthermore, salvation is clearly by grace through faith (Eph. 2:8) and no degree of repentance divorced from faith can be said to save anyone (e.g. Matt. 27:3-5; 2 Cor. 7:9-10)
But true saving faith, while not simply a synonym for repentance, undoubtedly includes the element of repentance. The emphatic teaching of Scripture is that “God now commands all men everywhere to repent” (Acts 17:30). Hence, faith and repentance should be viewed as two sides of the same coin, with faith being the “positive” side and repentance being the “negative” side. While repentance departs from unbelief in the gospel, faith is the positive inclination toward trust in the gospel. Repentance is “leaving there,” while faith is “coming here.”
Another way to look at faith and repentance is through the law of non-contradiction. The Bible describes saving faith as “being fully persuaded that what God has promised He is also able to perform” (Rom. 4:21). There are only two relationships a sinner can have in regards to Christ: either the sinner has saving faith in Christ or the sinner does not have saving faith in Christ. And to have saving faith in Christ is not the same as to not have saving faith in Christ.
Therefore, when a sinner exercises saving faith in Christ, he by that very act “repents” of the previous state of not having exercised saving faith in Christ. In other words, God’s call to repentance is the call to faith, and His call to faith is the call to repentance.