LORD, when thou wentest out of Seir, when thou marchedst out of the field of Edom, the earth trembled, and the heavens dropped, the clouds also dropped water.

Wesley's Notes

5:4 Edom - Seir and Edom are the same place; and these two expressions note the same thing, even God's marching in the head of his people, from Seir or Edom, towards the land of Canaan: while the Israelites were encompassing mount Seir, there were none of the following effects; but when once they had done that, and got Edom on their backs, then they marched directly forward towards the land of Canaan. The prophetess being to praise God for the present mercies, takes her rise higher, and begins her song with the commemoration of the ancient deliverances afforded by God to his people, the rather because of the great resemblance this had with them, in the miraculous manner of them. The earth trembled - God prepared the way for his people, and struck a dread into their enemies, by earth - quakes as well as by other terrible signs. Dropped water - That is, thou didst send storms and tempests, thunder and lightning, and other tokens of thy displeasure upon thine enemies.

Jamieson-Fausset-Brown Bible Commentary

4, 5. Allusion is here made, in general terms, to God's interposition on behalf of His people.

Seir . the field of Edom-represent the mountain range and plain extending along the south from the Dead Sea to the Elanitic Gulf.

thou wentest out-indicates the storm to have proceeded from the south or southeast.

Matthew Henry's Concise Commentary

5:1-5. No time should be lost in returning thanks to the Lord for his mercies; for our praises are most acceptable, pleasant, and profitable, when they flow from a full heart. By this, love and gratitude would be more excited and more deeply fixed in the hearts of believers; the events would be more known and longer remembered. Whatever Deborah, Barak, or the army had done, the Lord must have all the praise. The will, the power, and the success were all from Him.