Tertullian

“Two angels, however, appeared there.” For just so many honorary companions were required by the Word of God, which usually prescribes “two witnesses.” Moreover, the women, returning from the sepulcher and from this vision of the angels were foreseen by Isaiah, when he says, “Come, you women, who return from the vision”;2 that is, “come” to report the resurrection of the Lord.

Now the mystery of this "sign" was in various ways predicted; (a "sign") in which the foundation of life was forelaid for mankind; (a "sign") in which the Jews were not to believe: just as Moses beforetime kept on announcing in Exodus, saying, "Ye shall be ejected from the land into which ye shall enter; and in those nations ye shall not be able to rest: and there shall be instabilityof the print of thy foot: and God shall give thee a wearying heart, and a pining soul, and failing eyes, that they see not: and thy life shall hang on the tree before thine eyes; and thou shalt not trust thy life.