I have not written to you because you do not know the truth, but because you know it, and that no lie is of the truth.
1 John 2:21
Surrounding context
2:20 But you have an anointing from the Holy One, and you know all things.
2:21 I have not written to you because you do not know the truth, but because you know it, and that no lie is of the truth.
2:22 Who is a liar but he who denies that Jesus is the Christ? He is antichrist who denies the Father and the Son.