As the deer pants for streams of water,
so my soul pants for you, O God.

Psalm 42:1

“And here we have started up, and sent leaping over the plain another of Solomon’s favourites. What elegant creatures those gazelles are, and how gracefully they bound!… The sacred writers frequently mention gazelles under the various names of harts, roes, and hinds. …

I have seen large flocks of these panting harts gather round the water-brooks in great deserts of Central Syria, so subdued by thirst that you could approach quite near them before they fled.-” W.M.Thomson (1806-1896)

My soul thirsts for God, for the living God.
When can I go and meet with God?

Psalm 42:2

“The living God.” There are three respects especially in which our God is said to be the “living God.” First, originally, because he only hath
life in himself, and of himself, and all creatures have it from him. Secondly, operatively, because he is the only giver of life unto man. Our life, in the threefold extent and capacity of it, whether we take it for natural, or spiritual, or eternal, flows to us from God. Thirdly, God is said to be the “living God” by way of distinction, and in opposition to all false gods.- Thomas Horton (-1673)

My tears have been my food day and night,

while men say to me all day long,
“Where is your God?”

Psalm 42:3

“How powerfully do the scoffs and reproaches of the ungodly tend to shake the faith of a mind already dejected!

How peculiarly afflicted to the soul that loves God, is the dishonour cast upon him by his enemies!- “

Henry March (1791-1869)

These things I remember
as I pour out my soul:

how I used to go with the multitude,
leading the procession to the house of God,

with shouts of joy and thanksgiving
among the festive throng. Psalm 42: 4

This idea comes from The Treasury Of David Classic Reflections on the Wisdom of the Psalms by Charles H. Spurgeon Vol 1 pp. 276-279