A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
psa 114:1The writer briefly and beautifully celebrates God's former care of His people, to whose benefit nature was miraculously made to contribute. (Psa 114:1-8)
of strange language--(compare Psa 81:5).
psa 114:4skipped . . . rams-- (Psa 29:6), describes the waving of mountain forests, poetically representing the motion of the mountains. The poetical description of the effect of God's presence on the sea and Jordan alludes to the history (Exo 14:21; Jos 3:14-17). Judah is put as a parallel to Israel, because of the destined, as well as real, prominence of that tribe.
psa 114:5The questions place the implied answers in a more striking form.
psa 114:7at the presence of--literally, "from before," as if affrighted by the wonderful display of God's power. Well may such a God be trusted, and great should be His praise.