Carl Friedrich Keil and Franz Delitzsch Old Testament Commentary

The anointing of Solomon was carried out immediately, as the king had commanded. On the Crethi and Plethi see at Sa2 8:18. "The oil-horn out of the tent" (i.e., a vessel made of horn and containing oil) was no doubt one which held the holy anointing oil, with which the priests and the vessels of the sanctuary were anointed (see Exo 30:22.). The tent (האהל), however, is not the tabernacle at Gibeon, but the tent set up by David for the ark of the covenant upon Mount Zion (Sa2 6:17). For even though Zadok was appointed high priest at the tabernacle at Gibeon, and Abiathar, who held with Adonijah, at the ark of the covenant, the two high priests were not so unfriendly towards one another, that Zadok could not have obtained admission to the ark of the covenant in Abiathar's absence to fetch away the anointing oil.