God promises Moses: I am with you (or: I will be with you). It is not by the power or will of Moses that Israel will become free, it is only through the faithfulness and the strength of the Lord. These words are found throughout the Bible, often with the command: do not be afraid (e.g., when Joshua, the successor of Moses, is called, Joshua 1:9, cf. Deuteronomy 31:6).
12 He said, “But I will be with you, and this shall be the sign for you, that I have sent you: when you have brought the people out of Egypt, you shall serve God on this mountain.”