I know it sounds like a silly or weird question, but I'm serious.
One day Abraham said to his oldest servant, the man in charge of his household, “Take an oath by putting your hand under my thigh.
As the time of his death drew near, Jacob called for his son Joseph and said to him, “Please do me this favor. Put your hand under my thigh and swear that you will treat me with unfailing love by honoring this last request: Do not bury me in Egypt.
The right thigh must always be given to the priest who offers the blood and the fat of the peace offering.
On his robe at his thigh was written this title: King of all kings and Lord of all >lords.
Why is the thigh important?