John Trapp on Psalms 62:5

Verſ. 5. My ſoul, wait thou only upon God] They truſt not God at all, that is, not alone. He that ſtands with one foot on a Rock, and another foot upon a Quick ſand, will ſink and periſh, as certainly as he that ſtandeth with both feet on a Quickſand. David knew this, and therefore calleth earn and earneſtly upon his Soul, (for his buſineſs lay moſt within doors) to truſt only upon God. See verſ. 1.

For my expectation is from him] If he will not help me, none elſe ſhall; but it is he that ſaith, Look unto me and be ſaved, for I am God, and there is none elſe, Iſa. 45.22.