Mwanzo 17 : 19 Genesis chapter 17 verse 19

Mungu akasema, Sivyo, lakini Sara mkeo atakuzalia mwana wa kiume, nawe utamwita jina lake Isaka. Nami nitafanya agano langu imara kwake kuwa agano la milele kwa ajili ya uzao wake baada yake.
soma Mlango wa 17

God said, "No, but Sarah, your wife, will bear you a son. You shall call his name Isaac.{Isaac means "he laughs."} I will establish my covenant with him for an everlasting covenant for his seed after him.