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Rei
In Bible versions:
Rei: NET AVS NIV NRSV NASB TEV
a man who was one of David's military elite
my shepherd; my companion; my friend
my shepherd; my companion; my friend
Hebrew
Strongs #07472: yer Re`iy
Rei = "friendly"1) a person of David's court who remained loyal during Adonijah's
rebellion
7472 Re`iy ray-ee'
from 7453; social; Rei, an Israelite:-Rei.see HEBREW for 07453
Rei [EBD]
friendly, one who maintained true allegiance to king David (1 Kings 1:8) when Adonijah rebelled.
Rei [NAVE]
REI, an Israelite loyal to David at the time of the usurpation of Adonijah, 1 Kin. 1:8.REI [SMITH]
(friendly), a person mentioned (in (1 Kings 1:8) only) as having remained firm to David?s cause when Adonijah rebelled. (B.C. 1015.)REI [ISBE]
REI - re'-i (re`i, "friendly"; Rhesei): Rei, Shimei and the Gibborim who belonged to David are listed among those who did not join Adonijah in his attempt on the throne (1 Ki 1:8). The name is very uncertain. Winckler (Geschichte, II, 247) identifies him with Ira, the Jairite, who was a "priest to David" (2 Sam 20:26 the Revised Version margin); he tries to prove that this Ira (or Jair) was a priest of Bethlehem. Stade (GVI, I, 293, note 1) holds that Shimei and Rei were two officers of David's bodyguard. Josephus (Ant., VII, xiv, 4) has ho Daouidou philos, thus making Shimei a "friend," the courtier of 2 Sam 15:37; 16:16, and omitting Rei entirely. This would call for an original reading re`h ha-melekh, or re`eh ha-melekh, and is too wide a variant from the Massoretic Text. Assuming that Rei belongs in the text, it is safe to conjecture that he was an officer of the royal guard.Horace J. Wolf
Also see definition of "Rei" in Word Study