BECKET: Beauty is one of the few things which don’t shake one’s faith in God.

[Le beauté est une des rares choses qui ne font pas douter de Dieu.]

Jean Anouilh (1910-1987) French dramatist

Becket, Act 1 (1959) [tr. Hill (1960)]
    (Source)

The official English translation approved by Anouilh. (Source (French)). Alternate translations:

Beauty is one of the very few things that don't shake one's faith in God.
[tr. Raphael and Raphael (2004)]

Beauty is one of the rare things that do not lead to doubt of God.
[Frequently found translation, but source unknown]