Isaac is the second son of Abraham and the first son of Abraham’s wife, Sarah. In Gen 22, he is the victim of attempted sacrifice, an event that perhaps prompts Sarah’s death. Isaac subsequently marries a cousin, Rebekah. They have two children: Jacob and Esau.

There are unexpected patterns in the lives of Abraham and Isaac as told in Genesis, e.g., both of them seek refuge in Egypt, each attempting to pass off his wife as his sister. This has prompted considerable debate, with some scholars arguing that the writers of Genesis were merging different sets of ancestor stories.

Further reading

An entertaining summary of recent debate about Isaac can be seen in his ‘virtual letter’ to Abraham, composed by Yvonne Sherwood and published as part of a collection edited by Philip R. Davies: Sherwood, Y. “Letter 2: Isaac to Abraham.” Pages 5-22 in Yours Faithfully. BibleWorld. Sheffield: Acumen Publishing, 2004.
On the attempted sacrifice of Isaac, read Blenkinsopp, Joseph. Pages 140-60 in Abraham: The Story of a Life. Grand Rapids, MI; Cambridge, England: 2015.