This is a metaphor that means Jesus descended from David. Alternate translation: "who is a descendant of David" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Here to raise up is an idiom for causing someone who has died to become alive again. This can be stated in active form. Alternate translation: "whom God caused to live again" or "whom God raised from the dead" (See: [[rc://en/ta/man/translate/figs-activepassive]] and [[rc://en/ta/man/translate/figs-idiom]])
Paul speaks of the gospel message as if it were especially his. He means that this is the gospel message that he proclaims. Alternate translation: "according to the gospel message that I preach" (See: [[rc://en/ta/man/translate/figs-metonymy]])