Exodus 3:12

12 And God spoke to Moses, saying, I will be with thee, and this shall be the sign to thee that I shall send thee forth, —when thou bringest out my people out of Egypt, then ye shall serve God in this mountain.

Exodus 3:12 Meaning and Commentary

Exodus 3:12

And he said, certainly I will be with thee
To encourage and strengthen him; to protect, defend, and preserve him, and to succeed and prosper him; to give him credit and respect with the people of Israel, and influence over Pharaoh to prevail upon him at length to let Israel go: and this shall be a token unto thee that I have sent thee;
not the promise now made, nor the vision he had seen, but what follows: when thou hast brought forth the people out of Egypt, ye shall serve
God upon this mountain:
Mount Horeb or Sinai, as they did at the time of the giving of the law on it, when an altar was built upon a hill, and they offered burnt offerings and peace offerings, ( Exodus 24:4 Exodus 24:5 ) and this was a sign, "a posteriori", confirming the divine mission of Moses; and besides the promise of this, on which Moses might depend, being made by the Lord, assured him of success, that he should bring the children of Israel out of Egypt, since he and they would serve the Lord together at this mountain, and from whence he might conclude he had a mission and commission from God. Of a like kind is the sign or token given of the deliverance of Jerusalem from the army of Sennacherib, ( Isaiah 37:30 ) .

Exodus 3:12 In-Context

10 And now come, I will send thee to Pharao king of Egypt, and thou shalt bring out my people the children of Israel from the land of Egypt.
11 And Moses said to God, Who am I, that I should go to Pharao king of Egypt, and that I should bring out the children of Israel from the land of Egypt?
12 And God spoke to Moses, saying, I will be with thee, and this shall be the sign to thee that I shall send thee forth, —when thou bringest out my people out of Egypt, then ye shall serve God in this mountain.
13 And Moses said to God, Behold, I shall go forth to the children of Israel, and shall say to them, The God of our fathers has sent me to you; and they will ask me, What is his name? What shall I say to them?
14 And God spoke to Moses, saying, I am THE BEING; and he said, Thus shall ye say to the children of Israel, THE BEING has sent me to you.

The Brenton translation of the Septuagint is in the public domain.