John Gill Commentary Exodus 3:15

"And God said moreover unto Moses, Thus shalt thou say unto the children of Israel, Jehovah, the God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath sent me unto you: this is my name forever, and this is my memorial unto all generations." — Exodus 3:15 (ASV)

And God said moreover to Moses: As a further explanation of the above name, and of the design and use of it.

Thus shall you say to the children of Israel: For their further instruction in the said name, and for the confirmation of the mission of Moses, and the success of it: the Lord God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you; he who is Jehovah, and the covenant God of the ancestors of the people of Israel, and of them, so he is called, (Ecclesiastes 3:6).

This [is] my name for ever: Meaning either "Ehjeh, I am", in the preceding verse, or, which is the same, Jehovah in this, and so both of them, and including also the name of the God of Abraham which he was always to be known by.

And this is my memorial to all generations: The name by which he should be made mention of both by himself and others, and by which he would be called to remembrance by his people, and what he had promised to them, and done for them.