John 3:16 does not prove Sola Fide (and neither do Jn. 5:24 or 6:40)
Updated: Jul 10, 2022
By Luke Lancaster
Many of our Protestant brothers and sisters will attempt to prove their doctrine of Sola Fide by quoting this famous text from Scripture, "For God so loved the world that he gave his only Son, that whoever believes in him should not perish but have eternal life." This verse is rich in explaining how we are saved by our faith in Christ, but "faith" does not mean a purely mental belief.
Faith is both interior and exterior, not one or the other. The Greek word for "faith" is "pistis," which can be translated EITHER as "faith" or as "faithfulness" (Strong's Concordance, 4102). This understanding of faith is actually implied later on in John 3, where it says, "He who believes in the Son has eternal life; he who does not obey the Son shall not see life" (John 3:36). Believing is synonymous with obeying.
Steve Ray noted that the word used for “believe” (pisteuo) can be translated as ‘to obey’ according to Gerhard Kittel’s Theological Dictionary of the New Testament. This is because “faith” is a concise way of summing up the entire Catholic Faith. As the Council of Trent, Session 6, Chapter 8, says, “[F]aith is the beginning of human salvation, the foundation, and the root of all Justification; without which it is impossible to please God, and to come unto the fellowship of His sons.” Faith is the foundation of the entire Catholic religion, meaning that it holds up: good works (John 3:36, 5:29), repentance (Acts 2:38), baptism (John 3:5, 1 Peter 3:21), Eucharist (John 6:53), striving for holiness (Hebrews 12:14), avoiding serious sin (John 5:29, 1 Cor. 6:9-10), providing for relatives and family (1 Timothy 5:8), helping other people in need (Matt. 25:31-46), etc. Without these things, you do not have faith that will give eternal life, for faith leads to actions.
Another key point to consider is how John 3:16 says that those who believe "will have" eternal life - which is in the future tense. This is not a one-time only, "accept Jesus into your heart and you will be saved" moment. We have to live entire lives with faith, and only then will we receive "eternal life."
Protestants try to divorce faith from good works still, and they attempt to use John 3:16. But, their attempt is futile.