Beauty is indeed a good gift of God; but that the good may not think it a great good, God dispenses it even to the wicked.

[Quod bonum Dei quidem donum est; sed propterea id largitur etiam malis, ne magnum bonum uideatur bonis.]

Augustine of Hippo (354-430) Christian church father, philosopher, saint [b. Aurelius Augustinus]

City of God [De Civitate Dei], Book 15, ch. 22 (15.22) (AD 412-416) [tr. Dods (1871)]
    (Source)

Referencing Genesis 6:1-4, and of the "sons of God" who fell in love with the physical beauty of the women of the earthly city.

(Source (Latin)). Alternate translations:

Bodily beauty [...] is indeed a gift of God, but given to the evil also, lest the good should imagine it of any such great worth.
[tr. Healey (1610)]

Their beauty, in itself, was a gift of God, but it is the kind of gift which God gives even to the wicked so that good men may realize how slight a good it is.
[tr. Walsh/Monahan (1952)]

This beauty is indeed a good given by God, but he bestows it also on the wicked lest the good should regard it as a great good.
[tr. Levine (Loeb) (1966)]

Such beauty is certainly a good, a gift of God; but he bestows it on the evil as well as on the good for this reason, for fear that the good may consider it an important good.
[tr. Bettenson (1972)]

Such beauty is certainly a good, a gift from God; but He grants it to the evil also, lest it should come to seem too great a good to the good.
[tr. Dyson (1998)]

This good of beauty is indeed God's gift, but it is bestowed also on the wicked, so that it may not appear as a great blessing to those who are good.
[tr. Babcock (2012)]