Matthew Henry Commentary Psalms 74:12-17

"Yet God is my King of old, Working salvation in the midst of the earth. Thou didst divide the sea by thy strength: Thou brakest the heads of the sea-monsters in the waters. Thou brakest the heads of leviathan in pieces; Thou gavest him to be food to the people inhabiting the wilderness. Thou didst cleave fountain and flood: Thou driedst up mighty rivers. The day is thine, the night also is thine: Thou hast prepared the light and the sun. Thou hast set all the borders of the earth: Thou hast made summer and winter." — Psalms 74:12-17 (ASV)

The church silences her own complaints. What God had done for his people, as their King of old, encouraged them to depend on him. It was the Lord's doing; no one else could do it. This providence was food to faith and hope, to support and encourage in difficulties.

The God of Israel is the God of nature. He who is faithful to his covenant about the day and the night will never cast off those whom he has chosen. We have as much reason to expect affliction as to expect night and winter. But we have no more reason to despair of the return of comfort than to despair of day and summer. And in the world above, we will have no more changes.