Adriel (whose name means flock of God) was a nobleman in the ancient kingdom of Israel. Adriel was the son of Barzillai, the Meholathite, to whom Saul gave in marriage his daughter Merab (1 Sam. 18:19). The five sons that sprang from this union were put to death by the Gibeonites (2 Sam. 21:8, 9. Here it is said that Michal “brought up” [R.V., “bare”] these five sons, either that she treated them as if she had been their own mother, or that for “Michal” we should read “Merab“, as in 1 Sam. 18:19). Thus Adriel was the son-in-law of King Saul, and the brother-in-law of King David and Queen Michal, who raised Adriel’s children as their own.
In 2 Samuel 21:8 it states that Michal daughter of Saul had 5 sons with Adriel son of Barzillai. However in some translations, instead of Michal, it says Merab. Merab was the older daughter of Saul initially promised to David, but was instead given as wife to Adriel the Meholathite. Due to that later discrepancy that states Michal as the wife of Adriel instead of Merab as first said in 1st Samuel, many scholars believe this to be an ancient copyist error that should have read Merab in 2 Samuel 21:8