After the richness of revelation in the life of Abraham, it is rather surprising that in Isaac's adult life very little was added to what we have learned. He was the partial fulfilment of the promise to Abraham, and the continuity of God's purpose flowed through him, but there were no new elements. His life was primarily an interlude between Abraham and Jacob. He is the only patriarch whose name was not changed by God.
There is one recorded appearance of God to Isaac, in which God He briefly affirmed the promises made to Abraham.
"Do not be afraid, for I am with you; I will bless you and will increase the number of your descendants for the sake of my servant Abraham" (Gen 26:23-25).
Isaac lived among the Philistines and had the same quarrels with them that Abraham had. He pretended that Rebekah was his sister -- what is this fixation of the patriarchs? This theme is definitely overworked. Maybe Freud could help us here. He also quarreled with the Philistines over wells. He had prospered so much that Abimelech (the son of Abraham's ally?) sent him away. Yet later, a covenant of peace was forged between Isaac and Abimelech. This reaffirmed the agreement his father made with the same people (Gen 21:22-34).