He put a new song in my mouth lyrics

I think I can help you with that!

The song you're thinking of is probably "He Put a New Song in My Mouth" from the Bible, specifically Psalm 40:3 (NIV):

"He put a new song in my mouth, a hymn of praise to our God. Many will see and fear the Lord and put their trust in him."

This verse is often referenced in Christian worship and is a popular hymn or song in many churches. Does that sound right to you?