Exodus
King James Version (KJV)

“And I appeared unto Abraham, unto Isaac, and unto Jacob, by the name of God Almighty, but by my name JEHOVAH was I not known to them.”
King James Version (KJV)
6:1 With a strong hand - That is, being forced to it by a strong hand, he shall let them go.
6:2 l am Jehovah - The same with I am that I am, the fountain of being and blessedness, and infinite perfection. The patriarchs knew this name, but they did not know him in this matter by that which this name signifies. God would now be known by his name Jehovah, that is, A God performing what he had promised, and so giving being to his promises. A God perfecting what he had begun, and finishing his own work. In the history of the creation God is never called Jehovah, till the heavens and the earth were finished, #Gen 2:4|. When the salvation of the saints is compleated in eternal life, then he will be known by his name Jehovah, #Rev 22:13|, in the mean time they shall find him for their strength and support, El - shaddai, a God All - sufficient, a God that is enough.
6:5 I have heard the groaning of the children of Israel - He means their groaning on occasion of the late hardships put upon them. God takes notice of the increase of his people's calamities, and observes how their enemies grow upon them.