Yahweh speaks of the mountains, hills, and trees as if they were people with voices and hands, celebrating as Yahweh rescues his people. (See: [[rc://en/ta/man/translate/figs-personification]])
The words "thornbushes" and "brier" refer to species of plants that have sharp thorns growing on them. The words "cypress" and "myrtle" refer to species of evergreen trees. The thorny plants symbolize desolation, while the evergreens symbolize life and prosperity. (See: [[rc://en/ta/man/translate/translate-unknown]])
Something ceasing to exist is spoken of as if it were cut off, as a branch is cut off of a tree or a piece of fabric is cut off of clothing. This can be stated in active form. AT: "that will never end" or "that will last forever" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])