“Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne;”
King James Version (KJV)
2:30 #Psalm 89:4|, &c.
Ac 2:30 Knowing that God had sworn. God had promised to David that Christ should sit on his throne. See 2Sa 7:11-16 Ps 89:3,4,35,37 132:11.