Verses 17-19 deal with the events of the Israelites’ exodus from Egypt and the giving of God’s Law on Mount Sinai, but Moses is not mentioned by name in these verses.
And when thou didst lead his descendants out of Egypt: And when may be rendered “Later, when.” Contemporary English Version specifies that his descendants refers to “Jacob’s descendants” for clarity.
Thou didst bring them to Mount Sinai: Mount Sinai is the mountain where God came down to give Moses his Law during the Israelites’ escape from slavery in Egypt. For comments on this mountain, see 2 Esd 2.33, where it is called “Mount Horeb.”
An alternative model for this verse is:
• “Later, when you led Jacob’s descendants out of Egypt, you brought them to Mount Sinai.
Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Esdras. (UBS Helps for Translators). Miami: UBS, 2019. For this and other handbooks for translators see here.
