Proceeding immediately after to mix up and compare with one another things that are dissimilar, and incapable of being united, he subjoins to his statement regarding the sixty or seventy angels who came down from heaven, and who, according to him, shed fountains of warm water for tears, the following: “It is related also that there came to the tomb of Jesus himself, according to some, two angels, according to others, one;” having failed to notice, I think, that Matthew and Mark speak of one, and Luke and John of two, which statements are not contradictory. For they who mention “one,” say that it was he who rolled away the stone from the sepulchre; while they who mention “two,” refer to those who appeared in shining raiment to the women that repaired to the sepulchre, or who were seen within sitting in white garments. Each of these occurrences might now be demonstrated to have actually taken place, and to be indicative of a figurative meaning existing in these “phenomena,” (and intelligible) to those who were prepared to behold the resurrection of the Word. Such a task, however, does not belong to our present purpose, but rather to an exposition of the Gospel.
Source: Against Celsus (New Advent)