I provided light for you from a pillar of fire: See Exo 13.21. A pillar of fire provided light for the Israelites at night while they traveled through the wilderness. This clause may be rendered “I provided you with light from a pillar of fire,” “I caused fire in the form of a column to give you light [or, to shine light on you],” or “I gave you a flaming fire to light your way” (Contemporary English Version).

And did great wonders among you may be translated “and you watched as I did great things for you” (Contemporary English Version).

Yet you have forgotten me: See the comments on 2Esdras 1.6.

Says the Lord: This formula introduces a formal declaration, or pronouncement, from God, emphasizing that it is an authoritative and important message. As a rule this expression usually comes at the end of a saying, but it can also appear at the beginning or middle. Since the Lord is speaking here, Good News Bible makes this clear by saying “I, the Lord, have spoken.”

Good News Bible provides an excellent model for this verse.

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.