With ten thousand men at his feet That is, following him as their leader. Possibly it also intimates that they were all footmen, there being no horses in Judea but what were brought out of other countries. This made the victory the more glorious, by the overthrow of a vast number of chariots and horses in the opposite army.
Related Commentaries of Judges 4:10
Judges 4:10
10 And Barak called Zebulun and Naphtali to Kedesh; and he went up with ten thousand men at his feet: and Deborah went up with him.