Consider this verse: Exodus 15:2 The Lord is my strength and my song, and he has become my salvation; this is my God, and I will praise him, my father’s God, and I will exalt him. In this verse, it does not say to “pray for strength”, it says the Lord is my strength. So the prayer for strength is simply to say “The Lord is my strength”. Just say this a few times, and the realization will hit you, it’s not asking for strength, it’s declaring the fact about where our strength comes from. Our strength is not a thing, but a person Jesus Christ. This is the best prayer for strength.