'Line' in the Bible

This is what he let me see: and I saw the Lord stationed by a wall made straight by a weighted line, and he had a weighted line in his hand.

And the Lord said to me, Amos, what do you see? And I said, A weighted line. Then the Lord said, See, I will let down a weighted line among my people Israel; never again will my eyes be shut to their sin:

So this is what the Lord has said: Your wife will be a loose woman in the town, and your sons and your daughters will be put to the sword, and your land will be cut up into parts by a line; and you yourself will come to your end in an unclean land, and Israel will certainly be taken away a prisoner out of his land.