Adam Clarke on Psalms 31:19

O how great is thy goodness - God's goodness is infinite; there is enough for all. enough for each, enough for evermore. It is laid up where neither devils nor men can reach it, and it is laid up for them that fear the Lord; therefore every one who trembles at his word, may expect all he needs from this Fountain that can never be dried ufp.

Which thou hast wrought - Thou hast already prepared it; it is the work of thy own hands; thou hast provided it and proportioned it to the necessities of men, and all who trust in thee shall have it. And for them especially it is prepared who trust in thee before men - who boldly confess thee amidst a crooked and perverse generation.