What does Isaiah 16:3 mean?
The survivors of the slaughter of Moab's cities are on the run. Their invaders may have been the Assyrian army. These refugees travelled south into the nation of Edom to escape the massacre. Now they are asking Judah for asylum until it is safe to return to their own land (Isaiah 16:1–2). The request itself begins here.The people of Moab (Genesis 19:34–37) are neighbors of Judah, living on the west side of the Dead Sea. Historically, the Moabites were frequent enemies of Israel (Numbers 23:7; 25:1; Judges 3:12–14; 2 Kings 3:5). The people of Moab reach out to the leaders of Judah and ask them to "give counsel" or "declare your decision." They ask for justice or fairness for those on the run from harm.
Using poetic language that would have been well understood by all desert-dwellers, the Moabites make their request. They ask Judah to make a "shade for them" that is as dark as night even during the middle of the day. The picture is of a rock overhang or cave in the middle of a blisteringly sunny day in the desert. Covering, including from the sun, is a common biblical metaphor for physical protection (Psalm 17:8; Isaiah 51:6).
Finally, the Moabites ask the leaders of Judah to allow these fleeing people to conceal themselves, without revealing them to their enemies. The remnant of Moab wants Judah to let them hide out in their territory.