כבוד אלוהים הסתר דבר

The glory of G-d is to conceal a matter (Proverbs 25:2)

This impels the initiate not to discourse about or meditate on the sefirot excessively.

"Do not allow your mouth to cause your flesh to sin" (Eccl. 5:5). Silence is necessary to prevent the transmission of secrets that portend the inherently inscrutable dimension of Divine Reality, even if permission has been granted to contemplate them. Indeed the contemplation thereof leads one to discernment that these matters are beyond comprehension."
    — Azriel of Gerona

Zoharic Kabbalah: "Reserve to hide secrets is juxtaposed to the modesty of covering one's genitals". The inappropriate disclosure of esoteric wisdom is on par with sexual improprieties.

R' Isaac applied the sin of mouth to flesh to the transgression of explicating matters of Torah that one did not receive directly from his master, a transgression that is likened to the prohibition against making idols and/or worshipping images.

חָטָה - to sin
חוטן - sinner
חוטא ומחטיא את הרבים - sinning and causing the multitude to sin
אין אדם חוטא ולא לו - no man sins except for his own advantage
אל אחטָא בלשׁון - let me not sin by word of mouth
חיטֵא - purify, disinfect, make sin offering
חַת - fear, terror
חַתַה - abhore, recoil from
חתך - cut