Theology is an effort to explain the unknowable by putting it into terms of the not worth knowing.

H. L. Mencken (1880-1956) American writer and journalist [Henry Lewis Mencken]

A Little Book in C Major, ch. 7, § 11 (1916)
    (Source)

Variants:

THEOLOGY. An effort to explain the unknowable by putting it into terms of the not worth knowing.
[A Book of Burlesques, "The Jazz Webster" (1924)]

Theology -- An effort to explain the unknowable by putting it into terms of the not worth knowing.
[Chrestomathy, ch. 30 "Sententiae" (1949)]