1 Samuel 14:51

14:51 Kish was the father of Saul, and Ner the father of Abner was the son ¹  of Abiel.

1 Samuel 14:50

14:50 The name of Saul’s wife was Ahinoam, the daughter of Ahimaaz. The name of the general in command of his army was Abner son of Ner, Saul’s uncle. ² 

1 Samuel 26:5

26:5 So David set out and went to the place where Saul was camped. David saw the place where Saul and Abner son of Ner, the general in command of his army, were sleeping. Now Saul was lying in the entrenchment, and the army was camped all around him.

1 Samuel 26:14

26:14 David called to the army and to Abner son of Ner, “Won’t you answer, Abner?” Abner replied, “Who are you, that you have called to the king?”

[14:51]  ¹ tn 1 Chr 9:35-36 indicates that Jeiel (= Abiel?) had two sons (among others) named Ner and Kish (see also 1 Sam 9:1 and 1 Chr 8:30, where some Greek manuscripts include the name Ner, though it is absent in the Hebrew text). If this Kish was the father of Saul and Ner was the father of Abner, then Saul and Abner were cousins. However, according to 1 Chr 8:33 and 9:39, Ner, not Abiel, was the father of Kish. In this case, Kish and Abner were brothers and Abner was Saul’s uncle. The simplest solution to the problem is to see two men named Kish in the genealogy: Abiel (Jeiel) was the father of Ner and Kish I. Ner was the father of Abner and Kish II. Kish II was the father of Saul. The Kish mentioned in 1 Sam 9:1 was the father of Saul (v.2) and must be identified as Kish II. In this case the genealogy is “gapped,” with Ner being omitted. Abiel was the grandfather of Kish II.

[14:50]  ² sn The word “uncle” can modify either Abner or Ner. See the note on the word “son” in v. 51 for further discussion.