Gen 36 & 37 – The message is that marriage to unbelievers or pagans is prohibited.

Gen 36:1
Now these are the records of the generations of Esau (that is, Edom).

Gen 36:2
Esau took his wives from the daughters of Canaan: Adah the daughter of Elon the Hittite, and Oholibamah the daughter of Anah and the granddaughter of Zibeon the Hivite;

Gen 36:3
also Basemath, Ishmael's daughter, the sister of Nebaioth.

Esau had three wives. Two of them were from the daughters of Canaan. Rebekah and Isaac were disturbed with these two pagan wives of their son.

Gen. 26:34
And when Esau was forty years old he married Judith the daughter of Beeri the Hittite, and Basemath the daughter of Elon the Hittite;

Esau never should have married these women. It is against Torah to marry Canaanites

Deut. 7:1-4
“When the LORD your God shall bring you into the land where you are entering to possess it, and shall clear away many nations before you, the Hittites and the Girgashites and the Amorites and the Canaanites and the Perizzites and the Hivites and the Jebusites, seven nations greater and stronger than you, 2and when the LORD your God shall deliver them before you, and you shall defeat them, then you shall utterly destroy them. You shall make no covenant with them and show no favor to them. 3“Furthermore, you shall not intermarry with them; you shall not give your daughters to their sons, nor shall you take their daughters for your sons. 4“For they will turn your sons away from following Me to serve other gods; then the anger of the LORD will be kindled against you, and He will quickly destroy you.
The drash, remez, or maybe even pashat message is that marriage to unbelievers or pagans is prohibited. It is not a suggestion. It is the Torah, or instructions, of Elohim. But that was obviously not a concern with Esau.
River Valley Torah Assembly