Bible Verses About Sincerity: Our service to God

Now therefore fear the Lord, and serve him with a perfect and most sincere heart: and put away the gods which your fathers served in Mesopotamia and in Egypt, and serve the Lord.

But the hour cometh and now is, when the true adorers shall adore the Father in spirit and in truth. For the Father also seeketh such to adore him.

God is a spirit: and they that adore him must adore him in spirit and in truth.