Psalms 18:31 - Matthew Poole's English Annotations on the Holy Bible

It must needs be as I have said, because our Lord is the only God, and therefore there is none, neither God nor creature, that can hinder him from accomplishing his own word and work, or from defending those that trust him: he is unchangeable and invincible. Or this is an amplification, As God is what I have now described him to be, so he only is such, and there is no other God or Rock in which they may safely trust.