Sola Fide
Sola fide teaches that man is justified by faith alone, without works: believing in Christ would suffice for salvation, and his deeds would add nothing. Scripture says the contrary, and it says so in the very words that seemed to grant this thesis.
The only words “faith alone”
The expression “faith alone” appears only once in all of Scripture, and there it is denied, word for word. “You see that a man is justified by works, and not by faith alone.” James 2:24 The one passage where the Bible joins these two words at once separates them: it expressly refuses that faith alone justifies.
A dead faith does not save
Faith that produces nothing is without life, and what is dead does not save. “What good is it if someone says he has faith but does not have works? Can that faith save him?” James 2:14 Even the demons believe, and that does not save them. “You believe that there is one God; you do well. The demons also believe, and they tremble.” James 2:19 To believe that God exists and that Christ is Saviour, without that faith showing itself in deeds, is the faith of demons. “Faith without works is dead.” James 2:26
The faith that works through love
What saves is faith made alive by love. “What counts is faith working through love.” Galatians 5:6 A faith without charity, even entire, is worth nothing. “If I had all faith, so as to move mountains, but had not charity, I am nothing.” 1 Corinthians 13:2 Faith alone, cut off from the charity and the works it inspires, is precisely the faith Scripture declares unable to save.
What Scripture truly excludes
It is objected that Scripture elsewhere sets faith against works and justifies man without them. “Man is justified by faith, apart from the works of the law.” Romans 3:28 But the works set aside here are the works of the law, circumcision and the rites of the Old Covenant, and every claim to merit the first grace by oneself, as a wage owed. “To the one who works, the wages are counted as a debt, not as a gift.” Romans 4:4 Salvation begins by pure grace, which none can buy. “By grace you have been saved, through faith; and this is not from yourselves, it is the gift of God, not from works, so that no one may boast.” Ephesians 2:8-9 What Scripture excludes is the man who would save himself by his own powers and boast of it; what it requires is the faith that, once grace is received, works through charity. Abraham shows it: believing and justified, he is so also in the act of offering his son, his faith made perfect by works. “Faith was working with his works, and by works faith was made perfect.” James 2:22
Judged by works
On the last day, each will be judged on what he has done, which would make no sense if faith alone sufficed. “The Son of Man will repay each according to his works.” Matthew 16:27 Christ describes this judgement by the deeds done or neglected toward the least, and on these he separates the saved from the lost. “What you did to one of the least of these my brethren, you did to me.” Matthew 25:40 To believe does not dispense from acting, and Christ says so himself. “Not everyone who says to me, Lord, Lord, will enter the kingdom of heaven, but the one who does the will of my Father.” Matthew 7:21
Made righteous, not merely declared
God makes man righteous by giving him his grace, which renews him within and pours charity into him. Justification is not reduced to an outward declaration that would leave man as he was: God does not cover sin, he heals it. “The love of God has been poured into our hearts by the Holy Spirit who has been given to us.” Romans 5:5 The grace thus received acts, loves and works: the faith that saves therefore always carries with it the charity and the works it inspires.