Acts 15:5

The Pharisees; though converted to Christianity, they still retained their attachment to many rites and ceremonies of the Jewish dispensation. The errors of men are not all at once removed by their conversion: they need further instruction, observation, and experience, as well as the continued teaching of the Holy Spirit. But if they are really born of God, and use proper means, he will enlighten them; and as they see their errors they will renounce them, and become more and more conformed in faith and practice to his revealed will.