ונכללת ונרמזת באות ה׳ אחרונה של שם ה׳

This [attribute of sovereignty] is contained and represented in the final hei of the Tetragrammaton, in the following manner:

כי פנימיות ומקור הדבור הוא ההבל העולה מן הלב, ומתחלק לה׳ מוצאות הפה: אחה״ע מהגרון וכו׳

The internal aspect and the source of speech is the breath that rises from the heart, then is particularized into the five oral articulations (five being the numerical equivalent of the letter hei). [One of these produces the bracket of letters] alef, chet, hei and ayin from the throat, another produces the bracket of letters beit, vav, mem and pei from the lips, and so on.

At any rate, the internal aspect of speech is breath.

וגם הברת הה״א היא בחינת הבל לבד

In particular, the enunciation of the letter hei is solely unvocalized breath,

כמו שכתוב: אתא קלילא דלית בה מששא

as in the phrase,34 “A light letter without substance.”

Emanating, as it does, solely from the breath, it alludes to the level of Malchut and speech whose internal aspect is “breath”.