Psalm 18:45-50 is a declaration by David, who had sinned against both God and his fellow man, of Who his God IS!
David grasped what many born again believers fail to! Our God is NOT measured by human standards! He IS the STANDARD! Once David repented before the Lord for his sin (a selfish decision to do things MY way rather than God's way), he knew that His God was not a man that He should ever lie! David knew that the Covenant keeping God would ALWAYS have his back! Today's born again, spirit-filled believers NEED to get these TRUTHS firmly down on the inside of us! We CANNOT operate successfully in this world without knowing and having confidence in who WE are: IN HIM! And WE have a Covenant that is SO MUCH BETTER than David had! So, let's get busy studying to show ourselves approved unto God, rightly dividing the Words of HIS TRUTH! Then, once we have settled it in our own hearts that we ARE who HE says we are, let's start acting like the SAVED, ANOINTED, CALLED, SEPARATED, GIFTED, MIRACULOUSLY FORMED and CELEBRATED vessels of HIS glory! AMEN! Here is Hillsong with "Who You Say I AM":
Shalom in Him!