2 Samuel 3:25

25 Knowest thou not (that) Abner, the son of Ner, for hereto he came to thee, that he should deceive thee, and that he should know thy going out and thine entering, and should know all things which thou doest? (Thou must know that Abner, the son of Ner, came to thee so that he could deceive thee, and learn thy going out and thy coming in, and so know all the things that thou doest.)

2 Samuel 3:25 Meaning and Commentary

2 Samuel 3:25

Thou knowest Abner the son of Ner
Thou canst not be ignorant what a cunning deceitful man he is, nor of his designs; or dost thou not know? art thou ignorant? so read the Septuagint, Vulgate Latin, Syriac, and Arabic versions, with an interrogation:

that he came to deceive thee:
with false hopes, or to lead into wrong measures with an intention to involve and ruin him:

and to know thy going out, and coming in;
the affairs of his court, the secrets of his government, to observe his conduct and behaviour, and all his actions, and improve them against him:

and to know all that thou doest;
he suggests that he came not as a friend, but as a spy, and therefore ought to have been taken up, and detained, and not dismissed. This Joab said to set David against him, fearing, if he should be received into favour, he would be a rival of his; and besides his breast was full of revenge against him for the death of his brother.

2 Samuel 3:25 In-Context

23 And Joab, and the hosts that were with him, came afterward; therefore it was told to Joab of tellers, (saying,) Abner, the son of Ner, came to the king, and the king let go him, and he went forth in peace. (And so Joab, and the men who were with him, came shortly thereafter; and people said to Joab, Abner, the son of Ner, came to the king, and the king let him go away, with a guarantee of safety.)

24 And Joab entered to the king, and said, What hast thou done? Lo! Abner came to thee; why lettest go thou him (why hast thou let him go), and he went, and departed from thee?

25 Knowest thou not (that) Abner, the son of Ner, for hereto he came to thee, that he should deceive thee, and that he should know thy going out and thine entering, and should know all things which thou doest? (Thou must know that Abner, the son of Ner, came to thee so that he could deceive thee, and learn thy going out and thy coming in, and so know all the things that thou doest.)

26 Therefore Joab went out from David, and sent messengers after Abner; and led him again from the cistern of Sirah (and they brought him back from the Well of Sirah), while David knew not.

27 And when Abner had come again into Hebron, Joab led him asides half to the middle of the gate, (as if) that he should speak to him in guile; and he smote Abner there in the share-bone, and he was dead, into vengeance of the blood of his brother Asahel (and Joab struck, or stabbed, Abner in the belly, and he died there, in revenge for killing Joab's brother Asahel).