en_tn_condensed/isa/43/10.md

You ... my servant

Here "you" is plural and refers to the people of Israel. The phrase "my servant" refers to the nation, as a whole. (See: rc://en/ta/man/jit/figs-you)

Before me ... after me

In speaking this way, Yahweh is not saying that there was a time before which he did not exist or a time after which he will not exist. He is asserting that he is eternal and that the gods whom the people of other nations worship are not.

Before me there was no god formed

Here the word "formed" indicates that Yahweh is speaking of idols that people have made. This can be stated in active form. Alternate translation: "None of the gods whom people have formed existed before me" (See: rc://en/ta/man/jit/figs-explicit and rc://en/ta/man/jit/figs-activepassive)

there will be none after me

"none of those gods will exist after me"