en_tn_condensed/isa/44/23.md

Sing, you heavens ... glory in Israel

Here Isaiah speaks various parts of creation as if they were people and commands them to praise Yawheh.

you depths of the earth

"you lowest parts of the earth." Possible meanings are 1) that this refers to very deep places on the earth such as caves or canyons and forms a merism with "heavens" in the previous phrase or 2) that this refers to the place of the dead.