Augustine of Hippo, on Acts 2:3

“And there appeared to them parted tongues as it were of fire, and it sat upon every one of them:”

“Therefore, when he sent the Holy Spirit he manifested him visibly in two ways—by a dove and by fire: by a dove upon the Lord when he was baptized, by fire upon the disciples when they were gathered together.… The dove shows that those who are sanctified by the Spirit should be without guile. That their simplicity should not continue cold is shown us by the fire. Nor let it trouble you that the tongues were divided; for tongues are diverse, therefore the appearance was that of cloven tongues. "Cloven tongues," it said, "as of fire, and it sat upon each of them." There is a diversity of tongues, but the diversity of tongues does not imply schisms. Do not be afraid of separation in the cloven tongues, but in the dove recognize unity.”

Imported from an open dataset — not yet checked against the printed edition.