1 John 2:4-6 he that says, he knows him, and does not keep his commandments, is a lyar, and an enemy to the truth:

Mace⁽ⁱ⁾ ⁴ he that says, he knows him, and does not keep his commandments, is a lyar, and an enemy to the truth: ⁵ but he that observes his precepts, loves God with a true and perfect love: 'tis by this we know that we are truly christians. ⁶ he that says he is attach'd to Christ, ought to regulate his conduct by his example.