His father had not displeased him at any time This is mentioned as David's great error, and the occasion of Adonijah's presumption. In saying, Why hast thou done so? He had neither restrained him from, nor reproved him for his miscarriages, which David knew was a great sin. He also was a very goodly man This was a second ground of his confidence, because his great comeliness made him amiable in the people's eyes. His mother bare him after Absalom This is mentioned as a third reason why he expected the crown. Absalom being dead, he was next to him in order of birth. See 2 Samuel 3:3-4. He conferred with Joab and with Abiathar Whom it is likely he knew to be two discontented persons; the former on account of David's putting Amasa in his place, and the other because he saw Zadok in greater favour than himself. They helped him Probably, not so much because they thought the right of the crown was his, as with a view to oppose Solomon, and to secure and advance their own interest. It seems that God left them to themselves, to correct them for former miscarriages, with a rod of their own making.
Related Commentaries of 1 Kings 1:6
1 Kings 1:6-7
6 And his father had not displeased him at any time in saying, Why hast thou done so? and he also was a very goodly man; and his mother bare him after Absalom.
7 And he conferred with Joab the son of Zeruiah, and with Abiathar the priest: and they following Adonijah helped him.