Theodoret of Cyrus: Resurrection of the Faithful and Definition of the Faithful

And the dead in Christ will be raised first. He calls the faithful dead, not only those who have believed in the Gospel but also those who were illustrious before the Law; he said this also in the letter to the Hebrews, remember, "All these, though commended for their faith, did not gain what was promised, since God had foreseen something better in our case lest they be made perfect apart from us." So all conspicuous for their piety will be the first to enjoy resurrection; he taught this also in the letter to the Corinthians, "Christ the firstfruits, then those who are Christ's at his coming, then the end."

- Theodoret of Cyrus (around A.D. 393 to around A.D. 457), Commentary on the First Letter to the Thessalonians, Chapter 4, in Theodoret of Cyrus, Commentary on the Letters of St. Paul, Volume 2, p. 118 (2001), Robert C. Hill translator.