When discussing conditions of salvation, some will argue, "It doesn't matter what one believes or thinks, as long as he is sincere." This idea comes from the assumption that God could never condemn a person who means well. The Bible reveals God's will to us. We are not to rest the fate of our eternal soul upon an assumption.

Sincerity is important, but sincerity alone cannot save us. This fact is established very well by the conversion of Saul (the apostle Paul). "Then Paul, looking earnestly at the council, said, 'Men and brethren, I have lived in all good conscience before God until this day'" (Acts 23:1). There was not a day in Paul's life that he didn't believe he was serving God to the best of his ability. This included the time he spent persecuting the church (Acts 26:9; Gal. 1:13). Saul persecuted the church and tried to destroy it because he believed with all his heart it was the right thing for him to do. He was sincere in this effort, but that didn't make him right with God.

It does matter what a man thinks and believes. No amount of sincerity can change wrong into right or error into truth. Because of this, it also matters what a man is taught. The sincerity of the teacher or the hearer will not change false doctrine into truth. Jesus admonished His followers to "take heed what you hear" (Mark 4:24).

On the Last Day, man will be judged, not according to what he has thought, but according to what he has done. Jesus said:

"Not everyone who says to Me, 'Lord, Lord,' shall enter the kingdom of heaven, but he who does the will of My Father in heaven. Many will say to Me in that day, 'Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?' And then I will declare to them, 'I never knew you; depart from Me, you who practice lawlessness!'" (Matthew 7:21-23).

These individuals that Jesus speaks of are sincere. They acknowledge the Lord, and claim to be doing many good works in His name. However, their lack of obedience to the Father's will has resulted in them practicing lawlessness and being excluded from the kingdom of heaven. Notice, Jesus did not say, "but he who thinks he does the will of My Father in heaven." We must do the will of the Father. Sincerity alone is not enough.

Saul had to do something to change his relationship with God - "And now why are you waiting? Arise and be baptized and wash away your sins, calling on the name of the Lord" (Acts 22:16). Those who are truly sincere will do what the Bible says to do. They will not question, object, or protest the will of the Father. Neither will they remain purposely ignorant of His commands. It does matter what one believes and practices.