Verse 1-2
Psalms 114:1-2. When Israel went out of Egypt — That is, were brought out by mighty signs and wonders wrought by the power of God; from a people of a strange language — From a barbarous people, as some render it: though it is not improbable that the Israelites, though they stayed so long in Egypt, yet, having little converse or society with the Egyptians, knew little or nothing of their language. Judah was his sanctuary — The tribe of Judah is here put for the Jews in general, because Judah was their principal tribe. And they are said to have been his sanctuary and his dominion, because he appointed that a tabernacle should be placed for himself among them, promised to receive their homage and service, granted them a glorious token of his presence, and became their Lawgiver, King, and Governor, in a peculiar sense.

Verses 3-6
Psalms 114:3-6. The sea saw it, and fled — Saw that God was present with and among them in an extraordinary manner, and therefore fled; for nothing could have been more awful. Jordan is driven back — At the appearance of the divine glory which conducted them. “Although forty years intervened between the two events here mentioned, yet, as the miracles were of the same nature, they are spoken of together.” The mountains skipped like rams — Horeb and Sinai, two tops of one mountain, and other neighbouring hills and mountains. The same power that fixed the fluid waters, and made them stand still, shook the stable mountains, and made them tremble; for all the powers of nature are at the command and under the control of the God of nature. Mountains and hills are before God but like rams and lambs; even the largest and the most rocky of them are as manageable by him as the sheep are by the shepherd. The trembling of the mountains before Jehovah may shame the stupidity and obduracy of sinners, who are not moved at the discoveries of his glory. What ailed thee, O sea, that thou fleddest? — What was the reason, or for what cause was it, that thou didst, with such precipitation, retire and leave the middle of thy channel dry? Why didst thou, O Jordan, run back toward thy springs? Ye mountains, that ye skipped, &c. — Whence this unusual motion? Why did you leap like affrighted rams or lambs, as if you would have run away from the place where you had so long been fixed?

Verse 7-8
Psalms 114:7-8. Tremble, thou earth, at the presence of the Lord — But why do I ask these questions? Ye mountains and hills were no further moved than was quite just and proper, at the approach and presence of the great Jehovah. Yea, the whole earth had reason to tremble and quake on such an occasion. Which turned the rock into a standing water, &c. — For what cannot he do, who performs such an astonishing wonder as to turn rocks into streams and rivers, and flints into fountains of water? Well may we stand in awe of this God of almighty power, and well may we put our trust in this Being of boundless goodness, who, rather than his people should want what is necessary for their sustenance, will bring substantial bread out of the airy clouds, and refreshing waters out of the dry and flinty rocks!