Romans 2:18-21
2:18 and know his will and approve the superior things because you receive instruction from the law,
2:19 and if you are convinced that you yourself are a guide to the blind, a light to those who are in darkness,
2:20 an educator of the senseless, a teacher of little children, because you have in the law the essential features of knowledge and of the truth –
2:21 therefore you who teach someone else, do you not teach yourself? You who preach against stealing, do you steal?