David had fled from Saul's jealous anger to the High Priest Ahimelech, where David and his men were fed with the showbread, and David was given the sword of Goliath. Doeg was at Nob and witnessed Ahimelech's service to David.
Later, Saul asked about the whereabouts of David, and his herdsman spoke up:
- 1Sa 22:9 Then answered Doeg the Edomite, which was set over the servants of Saul, and said, I saw the son of Jesse coming to Nob, to Ahimelech the son of Ahitub.
However, Doeg omitted to inform King Saul that David had pretended to be on a secret mission on behalf of the king. He did not inform the king that Ahimelech was deceived by David, and that Ahimelech provided support because he thought he was serving the king.
Therefore Saul, with only part of the story, summoned the High Priest and his entire company and, in a rage, ordered them all killed. His officials refused to raise their hands against the priests and Saul turned to Doeg, who carried out the executions. Saul followed that up with an attack on the city of Nob, the city of the priests, and the families of the priests – men, women, and children – were put to the sword.
David later showed remorse for his part in the incident:
- 1Sa 22:22 And David said unto Abiathar, I knew it that day, when Doeg the Edomite was there, that he would surely tell Saul: I have occasioned the death of all the persons of thy father's house.
Also, see Psalm 52, which David wrote at the time Doeg the Edomite betrayed David's location to Saul.
In Rabbinical Literature
Doeg is the subject of many rabbinical legends, the origin of which is to be found in part in Psalm lii. Though he died at the early age of thirty-four years (Sanh. 69b), he is regarded by the rabbis as the greatest scholar of his time, the epithet () being supposed to have been applied to him because he made every one with whom he disputed "blush" (Midr. Teh. lii. 4; ed. Buber, p. 284). He could bring forward 300 different questions with reference to one single ritual case (Ḥag. 15b). But he was lacking in inward piety, so that God was "anxious () concerning his end, and "mourned" () for him (Sanh. 106b). His most unfortunate qualities, however, were his malice, jealousy, and calumnious tongue. He sounded the praise of David before Saul (I Sam. xvi. 18) only in order to provoke his jealousy, ascribing to David qualities that Saul lacked (Sanh. 93b; compare Midr. Shemuel. xix., end). He cherished a grudge against David, whose opinion prevailed over his own in determining the site for the Temple at Jerusalem (Zeb. 54b), and he had well-nigh succeeded in proving by his arguments that David, as a descendant of Ruth the Moabite, could not, according to the Law, belong to the congregation of Israel, when the prophet Samuel interposed in David's favor (Yeb. 76b, 77a; Midr. Shemuel xxii.). He also declared David's marriage with Michal to be invalid, and induced Saul to marry her to another.
Doeg not only disregarded the sanctity of marriage (), but he also slew with his own hands the priests of Nob, after Abner and Amasa, Saul's lieutenants, had refused to do so (Gen. R. xxxii.; Midr. Teh. lii. 4). As it often happens with those who strive for something to which they are not entitled, he lost that which he possessed (Gen. R. xx.). God sent the three "angels of destruction" () to Doeg; the first caused him to forget his learning, the second burned his soul, and the third scattered the ashes (Sanh. 106b; differently, Yer. Sanh. x. 29a). According to some he was slain by his own pupils when they found that he had forgotten his learning (Yalḳ., Sam. 131); others maintain that he was slain by David when he (Doeg) informed him of the death of Saul and of Jonathan (II Sam. i. 2; Pesiḳ., ed. Buber, iii. 28b; Ginzberg, "Die Haggada bei den Kirchenvätern," i. 38).
According to another Midrash, Doeg tried to preserve the life of Agag, the king of the Amalekites-Edomites, by interpreting Lev. xxii. 28 into a prohibition against the destruction of both the old and the young in war (Midr. Teh. lii. 4). Doeg is among those who have forfeited their portion in the future world by their wickedness (Sanh. x. 1; compare ib. 109b). Doeg is an instance of the evil consequences of calumny, because by calumniating the priests of Nob he lost his own life, and caused the death of Saul, Abimelech, and Abner (Yer. Peah i. 16a; Midr. Teh. cxx. 9 [ed. Buber, p. 504]).E. C. L. G. 
Ahimelech great-grandson of Eli (Bible); slain by Doeg the Edomite-fulfilling part of the curse on the House of Eli that none of his male descendants would live to old age. According to the Jewish Encyclopedia on David descendant Jehoash of Judah: In Rabbinical Literature: As the extermination of the male descendants of David was a divine retribution for the extermination of the priests by David (comp. I Sam. xxii. 17-21), Joash escaped death because in the latter case one priest, Abiathar, survived (Sanh. 95b).