'True God' in the Bible

And this is life eternal, to know thee, the only true God, and Jesus Christ whom thou has sent.

For they themselves declare concerning us what kind of entrance we had to you, and how you turned to God from idols, to serve the living and true God,

And we know that the Son of God has come, and has given us understanding, that we may know him that is true: and we are in him that is true, in his Son Jesus Christ. This is the true God, and life eternal. Little children, keep yourselves from idols.