The Italian Jews particularly enjoyed the genre of chidos, enigmas, and the author (R. Immanuel Hai Ricchi [1688-1743], Aderet Eliyahu, Livorno 1742) included a few at the end of this, mainly halachic, work.
The riddle describes a thing "that can burn aflame in water, all the sinners do it in secret" and so on. The answer is - AMOR. Love. Ricchi has a good time punning on "Amor" and המור, as in הר המור, a mount of spices, because both words sound alike (the Italian Jews, being Italian, did not pronounce the ה). Ricchi even helpfully explains that one must not wonder at this Romance word being used to explain Hebrew, for the Torah was given in four languages - Hebrew, Arabic, Aramaic, and Latin - according to the Sifre. The full line reads "He does not do this, who feareth the Lord. He is on a Mountain of Myrrh, and not a Mountain of Rupture." (That was my attempt to preserve the rhyme. His point is that har hamor, indicates amor, love, while har bater, indicates the opposite of love).