Why are you cast down, O my soul, and why are you in turmoil within me?
Hope in God; for I shall again praise him, my salvation and my God.
(Psalm 42:11 ESV)
The text says here O my soul , wait on God, hope in God, "for I shall yet praise him"; why? "for He is my God." Praise grows upon assurance.
Taken from the book A Lifting Up For The Downcast by William Bridge 1649