en_tn_condensed/isa/10/22.md

your people, Israel, are

Here "your" is singular. Possible interpretations are 1) God is speaking to Isaiah and "your" refers to Isaiah. AT: "your people Israel are" or 2) Isaiah or God is speaking to the nation of Israel and "your" refers to the nation. AT: "your people, O Israel, are" (See: rc://en/ta/man/translate/figs-you)

are like the sand of the seashore

This emphasizes that there were a great number of people of Israel. AT: "are too many to count, like the sand on the seashore" (See: rc://en/ta/man/translate/figs-simile)

Destruction is decreed

This can be stated in active form. AT: "Yahweh has decreed that he will destroy most of those who live in Israel" (See: rc://en/ta/man/translate/figs-activepassive and rc://en/ta/man/translate/figs-explicit)

as overflowing righteousness demands

This can be translated as a new sentence. AT: "This must be done for the sake of perfect righteousness" or "Yahweh must do this because he is completely righteous"