I have surely seen; Heb. In seeing, I have seen, i.e. I have seen and observed it diligently, accurately, and certainly; for so much the doubling of the verb signifies.
Related Commentaries of Exodus 3:7
Exodus 3:7
7 And the LORD said, I have surely seen the affliction of my people which are in Egypt, and have heard their cry by reason of their taskmasters; for I know their sorrows;