Albert Barnes Commentary Joshua 6:1

"Now Jericho was straitly shut up because of the children of Israel: none went out, and none came in." — Joshua 6:1 (ASV)

This verse is strictly parenthetical. It is inserted to explain the declaration begun (Joshua 5:14), and interrupted by Joshua’s question and obeisance (Joshua 5:14–15), but resumed in (Joshua 6:2).

Straitly shut up - See the margin, that is, not only shut, but barred and bolted.