The 1st baby that was born, his skin colour was a bit red. He also had hair all over his body, like an animal skin. Isaac and Rebekah named that baby Esau.
Rebekah’s older son Esau, his best clothes were in Rebekah’s tent, so Rebekah got those clothes and gave them to her younger son Jacob, and she told him to put them on.
So Isaac didn’t know that Jacob tricked him. He thought, “Now I know that this is Esau, because his arms are really hairy. I will eat that food that he made, and then I will ask God to be good to him as the next leader for our family.”