Yahweh speaks of himself by name to express the certainty of what he is declaring. See how you translated this in [Ezekiel 5:11](../05/11.md). Alternate translation: "this is what the Lord Yahweh has declared" or "this is what I, the Lord Yahweh, have declared" (See: [[rc://en/ta/man/jit/figs-123person]])
Here "mount up" means "rise up" and expresses that his wrath will increase. The words "wrath" and "anger" mean the same thing and emphasize how intense his anger will be. Alternate translation: "my anger will greatly increase" or "I will be very angry with you" (See: [[rc://en/ta/man/jit/figs-metaphor]] and [[rc://en/ta/man/jit/figs-doublet]])