Where do we find any reference that Abraham had 8 kids (Isaac, Ishmael, and 6 others from another woman)? I have recently heard this teacher saying that, but he didn’t specify the source.
According to 1 Chron. 1:32, Abraham had 6 sons with a woman named Ketura after Sarah died. They were Zimran, Jokshan, Medan, Midian, Ishbak and Shuah.
Jokshan had two sons named Sheba and Dedan who settled in the Arabian Peninsula. Some scholars believe they’re the ones referenced in Ezekiel 38:13 but others prefer the Sheba and Dedan of Genesis 10:7 who were grandsons of Cush.
In any case Sheba settled the southwestern edge of the Arabian Peninsula across the Red Sea from present-day Ethiopia. The Queen of Sheba visited Israel in the time of Solomon. Sheba is also known in history as Saba. The Sabeans conducted trade in spices with the other peoples of the ancient world.
Dedan was probably the habitat of the Arabs on the northern part of the Arabian Desert, which is modern-day Saudi Arabia. The ancient capital of Saudi Arabia is still called Dedan on many maps today.