Albert Barnes Commentary Judges 4:3

"And the children of Israel cried unto Jehovah: for he had nine hundred chariots of iron; and twenty years he mightily oppressed the children of Israel." — Judges 4:3 (ASV)

Oppressed - The same word is used (Exodus 3:9) of the oppression of Israel by the Egyptians. If they were put to task-work in hewing timber, their condition was very like that of their ancestors making bricks.