Sanctify them by the truth; your word is truth. –Jesus in John 17:17

“You are a king, then!” said Pilate. Jesus answered, “You say that I am a king. In fact, the reason I was born and came into the world is to testify to the truth. Everyone on the side of truth listens to me.” “What is truth?” retorted Pilate. With this he went out again. –John 18:37-38

—

Roger Olson, The Story of Christian Theology (InterVarsity Press, 1999).

Walter Martin, The Kingdom of the Cults (Bethany House Publishers, 1985).