2Sa 8:18 Benaiah the son of Jehoiada, a very brave hero of Kabzeel (see at 2Sa 23:20.), was over the Crethi and Plethi. Instead of והכּרתי, which gives no sense, and must be connected in some way with 1Ki 1:38, 1Ki 1:44, we must read הכּרתי על according to the parallel passage 2Sa 20:23, and the corresponding text of the Chronicles. The Crethi and Plethi were the king’s body-guard, σωματοφύλακες (Josephus, Ant. vii. 5, 4). The words are adjectives in form, but with a substantive meaning, and were used to indicate a certain rank, lit. the executioners and runners, like השּׁלישׁי (2Sa 23:8). כּרתי, from כּרת, to cut down or exterminate, signifies confessor, because among the Israelites (see at 1Ki 2:25), as in fact throughout the East generally, the royal halberdiers had to execute the sentence of death upon criminals. פּלתי, from פלת (to fly, or be swift), is related to פּלט, and signifies runners. It is equivalent to רץ, a courier, as one portion of the halberdiers, like the ἄγγαροι of the Persians, had to convey the king’s orders to distant places (vid., 2Ch 30:6). This explanation is confirmed by the fact that the epithet והרצים הכּדי was afterwards applied to the king’s body-guard (2Ki 11:4, 2Ki 11:19), and that הכּרי for הכּרתי occurs as early as 2Sa 20:23. כּרי, from כוּר, fodit, perfodit, is used in the same sense.
And David’s sons were כּהנים (“confidants”); not priests, domestic priests, court chaplains, or spiritual advisers, as Gesenius, De Wette, and others maintain, but, as the title is explained in the corresponding text of the Chronicles, when the title had become obsolete, “the first at the hand (or side) of the king.” The correctness of this explanation is placed beyond the reach of doubt by 1Ki 4:5, where the cohen is called, by way of explanation, “the king’s friend.” The title cohen may be explained from the primary signification of the verb כּהן, as shown in the corresponding verb and noun in Arabic (“res alicujus gerere,” and “administrator alieni negotii”). These cohanim, therefore, were the king’s confidential advisers.