દરિયાનો તાગ આવે, પણ છ તસુની છાતીનો તાગ આવે નહીં.

dariyānō tāga āvē, paṇa cha tasunī chātīnō tāga āvē nahīṁ.

Literally: The depth of the ocean can be measured, but the depth of a six-inch chest cannot.
What it means: Human nature is unfathomable.
The English proverb Shah set beside it: Still waters run deep.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1923) · 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.