Genesis 17:19

“And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my c...”

Genesis 17:21

“But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.”

Genesis 21:3

“And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac.”

Genesis 21:4

“And Abraham circumcised his son Isaac being eight days old, as God had commanded him.”

Genesis 21:5

“And Abraham was an hundred years old, when his son Isaac was born unto him.”