Charles Ellicott Commentary Amos 7:8

"And Jehovah said unto me, Amos, what seest thou? And I said, A plumb-line. Then said the Lord, Behold, I will set a plumb-line in the midst of my people Israel; I will not again pass by them any more;" — Amos 7:8 (ASV)

Pass by them—In the sense of sparing. There will come a time when prayer will be of no avail. All intercessions, however passionate or eager, will be too late. The door of mercy is shut.