David
Psalm 46:4ESV·traditional attribution

There is a river whose streams make glad the city of God, the holy habitation of the Most High.

John Calvin Reformed @genevareformer

PSALM 46 This psalm seems to be an expression of thanksgiving rather for some particular deliverance, than for the constant aid by which God has always protected and preserved his Church. It may be inferred from it that the city of Jerusalem. when stricken with great terror, and placed in extreme danger, was preserved, contrary to all expectation, by the unlooked for and miraculous power of God.

Commenting on Psalm 46:1-11

C.H. Spurgeon Reformed Baptist @princeofpreachers

There is a river. Divine grace like a smoothly flowing, fertilising, full, and never failing river, yields refreshment and consolation to believers. This is the river of the water of life, of which the church above as well as the church below partakes evermore.

Matthew Henry Presbyterian @wholebiblehenry

The psalmist here teaches us by his own example. I. To triumph in God, and his relation to us and presence with us, especially when we have had some fresh experiences of his appearing in our behalf (Psa 46:1): God is our refuge and strength; we have found him so, he has engaged to be so, and he ever will be so. Are we pursued?

Commenting on Psalm 46:1-5