Psalms 77:9

Hath God forgotten to be gracious
He has not, is it possible that he should? as the Targum; it is not; he cannot forget the purposes of his grace and mercy, nor the covenant and promises of it, nor people the objects of it; and much less can he for his grace and mercy itself, so agreeable to his nature, what he delights in, and which he has proclaimed in Christ:

hath he in anger shut up his tender mercies?;
as an avaricious man shuts up his hand, and will not communicate liberally; or as the sea is shut up with doors, that its waters may not overflow; no, the mercies of God are not restrained, though unbelief says they are, at least queries if they are not, ( Isaiah 63:15 ) , but Faith says they flow freely through Christ, and the people of God are crowned with lovingkindness and tender mercies; God gives liberally, and upbraideth not; and though he may hide his face in a little seeming wrath for a moment, yet with great mercies will he gather, and with everlasting kindness will he have mercy.

Selah. (See Gill on Psalms 3:2).