1 Kings 1:5

"Then Adonijah the son of Haggith exalted himself, saying I will be king: and he prepared him chariots and horsemen, and fifty men to run before him. And his father had not displeased him at any time, in saying, Why hast thou done so? and he was a very goodly man; and he was born after Absalom. And he conferred with Joab the son of Zeruiah, and with Abiathar the priest: and they following Adonijah helped him. But Zadok the priest, and Benaiah the son of Jehoiada, and Nathan the prophet, and Shimei, and Rei, and the mighty men that belonged to David, were not with Adonijah. And Adonijah slew sheep and oxen and fatlings by the stone of Zoheleth, which is beside Enrogei; and he called all his brethren the king's sons, and all the men of Judah, the king's servants: but Nathan the prophet, and Benaiah, and the mighty men, and Solomon his brother he called not."

It is clear from this paragraph that Adonijah was well aware of the fact that David had chosen Solomon to succeed him; and that alone can account for the fact that Solomon and other powerful persons closely associated with David were NOT invited to the big barbecue.

Another revelation which we should observe here is the fact of Adonijah's copying the procedure of Absalom by getting a chariot, horsemen, and fifty runners ahead of his carriage. Also, David's customary failure to discipline members of his family was a primary feature that aided the early stages of Adonijah's attempted coup d'etat. If he had succeeded, his very first action, no doubt, would have been the murder of Solomon.

The reason why Joab joined in this venture is not hard to discern. David had pronounced a curse upon him; and, he, no doubt, hoped to avoid any ultimate punishment by supporting Adonijah. Why Abiathar joined the Adonijah party is not so apparent. Some suppose that he was jealous of the preference David seemed to have conferred upon Zadok, a rival High Priest.