Justification by faith alone, and not by works, is the foundation of Christian theology. Often referred to as sola fide (“faith alone”), it is the pillar of the Protestant Reformation; many are devoted to preserving this core tenet of Christian belief: faith alone in Christ alone. (e.g. GES)
In searching the Bible for this concept, it is instructive to note that only a single verse contains both words, faith and alone, and clearly explains the relationship between them — James 2:17: “Even so faith, if it hath not works, is dead, being alone.” It tells us we’re not saved by faith alone; a faith that is alone is dead, not saving faith. (vs 14) The book of James apparently denies the doctrine of sola fide, at least as most would understand it; no wonder Martin Luther, the father of the Reformation, had difficulty accepting the inspired text.
Yet it would indeed be perilous to conclude that works are necessary for salvation, that we can somehow earn or merit salvation. Scripture clearly states otherwise: we’re saved by faith, and not by works. (Ga 2:16) Mixing faith/grace and works as grounds for salvation isn’t rational; as requirements they are mutually exclusive by definition; it must be one or the other. (Ro 11:6) How then do we parse this? We must be careful, thorough, and precise; we cannot afford to miss it. (2Pe 1:10-11)
It helps to begin by observing that Christ did not come to start a new religion, nor to teach us a new way to be saved: the way to Heaven has never changed. We’re saved just like Father Abraham and King David; Paul builds his case for justification by faith on the testimonies of these two men. (Ro 4:1-3, 6-8) Born again is not just a New Testament idea; it’s grounded in the Old Testament. (Jn 3:10)
It’s very easy to teach a new (and thus false) gospel by taking isolated NT passages out of context; look at the whole of Scripture. If we can’t see the Gospel in the Old Testament we don’t yet understand it, for this is how the apostle Paul taught it. (Ro 16:25-26)
Believing on Jesus Christ (Ge 15:6) is the supernatural work of God. (Jn 6:29) This divine work creates in us a new, transformed nature (Ga 6:15) that does not deliberately and willfully continue in sin. (1Jn 3:9-10) Those who do intend to continue living in sin don’t yet know God. (vs 6)
Thinking we can receive the gift of eternal life without receiving Christ Himself is deception: the gift is the Giver: Christ Himself is the Life we seek. (1Jn 1:1-2) To believe on Him is to receive Him as He is (Jn 1:12) and trust in Him (Ep 1:15); it is to love Him (1Co 16:22) and obey Him. (He 5:9)
So, we’re indeed saved only by faith (by faith alone), and saving faith is only in Christ (faith alone in Christ alone), but true faith is never alone: it does not exist in isolation, apart from works. Saving faith is always accompanied by a changed life. (He 6:9) It isn’t that we must change our life in order to believe on Christ, but experiencing faith in Christ will radically change us. Pursuing holiness won’t save us, but there’s no eternal life without it. (He 12:14) When we diligently seek God, we find Him (He 11:6) and He changes us. (Ep 2:10)