David
Psalm 86:3BSB·traditional attribution

Be merciful to me, O Lord, for I call to You all day long.

John Calvin Reformed @genevareformer

PSALM 86 In this psalm prayers and holy meditations, engaged in with the view of nourishing and confirming faith, together with praises and thanksgivings, are intermingled. It having been difficult in the judgement of carnal reason for David to escape from the distresses with which he was environed, he sets in opposition to its conclusions the infinite goodness and power of God.

Commenting on Psalm 86:1-17

C.H. Spurgeon Reformed Baptist @princeofpreachers

Be merciful unto me, O Lord. The best of men need mercy, and appeal to mercy, yea to nothing else but mercy; they need it for themselves, and crave it eagerly of their God as a personal requisite. For I cry unto thee daily. Is there not a promise that importunity shall prevail? May we not, then, plead our importunity as an argument with God?

Matthew Henry Presbyterian @wholebiblehenry

This psalm was published under the title of a prayer of David; not as if David sung all his prayers, but into some of his songs he inserted prayers; for a psalm will admit the expressions of any pious and devout affections.

Commenting on Psalm 86:1-7