If you want to be perfect, go, sell what you have and give to the poor, and you will have treasure in heaven. Then come, follow me. (Matthew 19:21)
Jesus did not call the rich young ruler a liar when he claimed to have kept the commandments from his youth. He who knows our thoughts took the young man at his word and told him what he still lacked just as he asked.
Jesus did not tell him, “What you lack is faith.” Jesus did not say to him, “What you need to do is believe.” He did not say anything remotely like these things. Instead He told the man what he should do: sell his possessions and give to the poor. How then can it be said that one can be saved by trusting in Christ alone — that nothing else can supplement nor supplant that single thing of trust in Christ?
How can this be? It is unreasonable to suggest that we should read back a particular interpretation of St. Paul into Christ’s words. If anything, we should read Christ’s words into what St. Paul said, particularly since there is good reason to think that St. Paul did not hold to sola fide as formulated by Protestants. It makes no sense to interpret the master by the disciple; we should interpret the disciple by the Master, since we have the Master’s words themselves. It is furthermore unreasonable to suggest that the words of Jesus in Matthew 19 are unclear, so that we should use clearer texts to help us understand Him. No. Jesus is perfectly comprehensible in Matthew 19 — if we do not make assumptions that obfuscate what He says there. He told the rich young ruler that he would have treasure in heaven if he sold his goods and gave to the poor. It may be reasonable to suppose that Jesus does not intend to exclude faith, but it is just absurd to say that the rich young ruler would not have treasure in heaven if he did exactly what Jesus said!