Exodus 3:12

12He said, aBut 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, byou shall serve God on this mountain.”

Exodus 3:18

18And cthey will listen to your voice, and you and the elders of Israel dshall go to the king of Egypt and say to him, ‘The Lord, the God of the Hebrews, has emet with us; and now, please let us go a three daysjourney into the wilderness, that we may sacrifice to the Lord our God.’
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