ધુત્તા હોય સલક્ષણા, વેશ્યા હોય સલજ્જ;

dhuttā hōya salakṣaṇā, vēśyā hōya salajja;

Literally: A cheat endowed with good qualities, a prostitute who is modest;
What it means: Certain things are inherently contradictory and untrustworthy by their very nature.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1921) · read from the scan by machine — the Gujarati itself is unchecked · English is machine-made and nobody has checked it yet

Heard it differently, or know we've got the sense wrong? Tell us — that is exactly the kind of correction this needs.