Abstract The author compares the well-known mythological figure of Narcissus contemplating his own image in the water with palindromes and “symmetric” numbers, that allow themselves to be read both ways with equal result, and points out the kabbalistic relevance of such “mirrorings” in the context of the “anagrammatic genius” of the hebrew sacred language. After stressing the fact that the paradigm of the mirror is common to oriental as well as western traditional metaphysical and religious speculation, he comes to mention the mysterious use of the number 515 by means of which Dante Alighieri, in his Divine Comedy, prophesies the advent of God's Envoy. Critical ingenuity has tried to explain why Dante chose this numerical cipher, with no great success. Yet, the author proves that the mystery of that “palindrome-number” becomes clear if it is considered in the light of the mirroring analogy, often practised by mystics, philosophers and poets. In fact, it results from the properties of the Pythagorean “sacred triangle” 3·4·5, if taken as a “Narcissic system”, as well as from the numbers expressing the angles of the “head” of a regular pentagon, again if taken after the mirror-paradigm. 515 proves to be the commutating factor between divine perfection above and its reflexion “in the waters”. The next concludes by choosing other instances of the use of this symmetric number, with analogous meaning, although rendered cryptic due to dangers of heresy and fear of the Inquisition, in works by Albrecht Du¨rer and in a Portuguese painting of the sixteenth century, attributed to Master Jorge Alfonso.