1) (fl. ? 19th-16th cent, BCE)
Israelite, son of Abraham and Sarah. He was born when Abraham was 100 years old (Genesis 21:5). He was the heir of the Abrahamic tradition and covenant (Genesis 17:19; 21:12). In order to test him, God ordered Abraham to sacrifice Isaac, but the boy was saved at the final moment (Genesis 22). Isaac married Rebekah, who bore him two sons, Esau and Jacob.
2) (fl. 8th-9th cent.)
Jewish merchant of Aachen. In 797 he was appointed by Charlemagne as guide and interpreter to an official delegation to Harun al-Rashid. When Charlemagne's ambas-sadors died on the way, Isaac completed the journey and was received by Charlemagne in audience when he returned after four years.
Dictionary of Jewish Biography. Dan Cohn-Sherbok.