This is a poetic device. It does not mean that a specific number of sins had been committed, but indicates that many sins had led to God's judgment. See how you translated these words in [Amos 1:3](./03.md).
Yahweh uses two negatives here to emphasize that he would punish them. See how you translated these words in [Amos 1:3](./03.md). (See: [[rc://en/ta/man/translate/figs-litotes]])
# their covenant of brotherhood
"the agreement they made to treat you as brothers"