We discussed Abraham and God’s commandment that he offer his own beloved son Isaac to be sacrificed in Gospel Doctrine today. I think most people assume Isaac was a young boy, but it is worth pointing out that he could have been anywhere from about 10 to 36. There are many Jewish traditions indicating Isaac was in his 30s at the time. Here are some things to consider:
At the time Isaac was conceived, Abraham was 99 years old and Sarah was 90 and Ishmael was 13 (Genesis 17:1, 17. 25). Ishmael was sent out of the household at the time Isaac was weaned, which would indicate Isaac was about two or three years old. Isaac was sacrificed sometime before Sarah died at the age of 127 (Genesis 23:1).
So, Isaac must have been taken to Mt. Moriah sometime between the age of about five and 36. He is referred to in the Bible by the name “lad,” which in Hebrew is na’ar. This same noun is used to describe Joseph at the age of 17 (Genesis 37:2) and at the age of 30 (Genesis 41:12, 46).
Isaac was old enough to travel three days with Abraham but without his mother. His conversation with his father is typical of that of a teenager or young man. Isaac is also old enough to carry the wood for the sacrifice up the mountain. So, the preponderence of evidence would indicate Isaac was a teenager or young man.
There are many Jewish traditions indicating Abraham was in his 30s at the time of his sacrifice.
Bottom line: we don’t know how old Isaac was for sure, but any claims that he was very young (say, less than 12) are probably incorrect.