God raised up (ho theos anestēsen). Est hoc summum orationis (Blass). Apparently this is the first public proclamation to others than believers of the fact of the Resurrection of Jesus. “At a time it was still possible to test the statement, to examine witnesses, to expose fraud, the Apostle openly proclaimed the Resurrection as a fact, needing no evidence, but known to his hearers” (Furneaux).
The pangs of death (tas ōdinas tou thanatou). Codex Bezae has “Hades” instead of death. The lxx has ōdinas thanatou in Psa 18:4, but the Hebrew original means “snares” or “traps” or “cords” of death where sheol and death are personified as hunters laying snares for prey. How Peter or Luke came to use the old Greek word ōdinas (birth pangs) we do not know. Early Christian writers interpreted the Resurrection of Christ as a birth out of death. “Loosing” (lusas) suits better the notion of “snares” held a prisoner by death, but birth pangs do bring deliverance to the mother also.
Because (kathoti). This old conjunction (kata, hoti) occurs in the N.T. only in Luke’s writings.
That he should be holden (krateisthai auton). Infinitive present passive with accusative of general reference and subject of ēn adunaton. The figure goes with “loosed” (lusas) above.