'Barrier' in the Bible

"You should fear me!" says the Lord. "You should tremble in awe before me! I made the sand to be a boundary for the sea, a permanent barrier that it can never cross. Its waves may roll, but they can never prevail. They may roar, but they can never cross beyond that boundary."

There was a barrier in front of the alcoves, 1? feet on either side; the alcoves were 10? feet on either side.