Regarding created beings, there are four elementals…

Present day science claims that there are over a hundred elements. In fact, it is not a contradiction. These four grand elements have many sub-divisions.

…and their mnemonic is alef-reish-mem-ayin

One whose predominant quality is love will merit worlds of resplendent seas and water castles.

whose gematria is 310. This is the number of worlds that the righteous inherit in the world-to-come. The significance of this is that each of these worlds has in it the four elements. The nature of each individual's set of worlds depends upon how he blended the elements in his service of G‑d while alive. For example, love manifests primarily from the element of water. One whose predominant quality is love will merit worlds of resplendent seas and water castles.1

…which stands for 'aish' [fire], 'Ruach' [wind], 'mayim' [water], and 'afar' [dust]. They are themselves an expression of the four letters of the the tetragrammaton as explained in the Zohar (Vaera 23b). From these four elements, which are hinted to by the four letters of the Tetragrammaton, all of physical creation was brought into existence.

The Infinite light shines to the four letters, and they shine to the four sides of the Divine chariot, which in turn shine to the four elements and the four angels in charge of them (Sefer Yetzira). Eventually, it all progressively descends and cascades down to become the four elements of the universe

Furthermore, the four letters of the tetragrammaton combine to make twelve permutations (Sefer Yetzira)...

A set of four members can be combined in sixteen ways (4x4). However, since one of the letters of the tetragrammaton (the hei) is repeated, it only combines twelve ways (4x3).

...and they continue to create even more combinations, each different from the other, in level and in number, until they total 600,000.

Each combination itself expands into further permutations, and they in turn expand more, until the total equals the amount of soul roots. Each name is a direct channel of Divinity. "The souls are one with G‑d." (Zohar). There are therefore the same amount of soul roots as the names that channel Divinity.

The tetragrammaton is the intrinsic name.

There are actually infinite categories of names. The tetragrammaton is however the intrinsic name; therefore the essential soul roots come from it.

These six hundred thousand combinations also have among them the four elements, and this is what allows various different combinations, which result in an unlimited amount of different creations — all from the four elements. However, [the] uniqueness [of any given name, or part of creation drawn from a name] will be based upon its predominant element, as the Rambam writes in [the first book of Mishna Torah], Hilchot Yesodei HaTorah, Chapter Four.

The souls of man, which are from the four [spiritual] elements, as mentioned.

From the elements come all of the quality traits. Tanya (Chapter 1) explains which traits come from which elements. This is the key to rectifying the personality The main job of a person in the world is to purify all of his qualities from their bad aspect (Shaar Kedusha). Fire must be cleansed from manifesting as anger, to be left as pure holy passion. Water needs to be purified from being drawn after lust, leaving it to shine in the soul as Divine delight. Wind must be separated from its negative aspect of energizing pride and idol chatter, to be left as a calm spirit. Dust requires cleansing from expressing as laziness and depression, to remain a channel for a proper measure of stoicism in the psyche.

Each of the four elements, in all of their combinations, total six hundred thousand. Therefore they divide into many parts, according to the permutations, each part being called a complete partzuf called 'man' [his supernal root].

This is a term for a complete spiritual organism, composed of two hundred and forty eight spirit limbs and three hundred and sixty fix spirit veins.

The division is unlimited. With this you can understand the secret of gilgul which is the reincarnation of the 'parts', and the arrival of each will depend upon the time appropriate for it.

When G‑d reincarnates a soul, a different Ruach is paired with a different Nefesh.

"When G‑d reincarnates a soul, a different Ruach is paired with a different Nefesh." (Sichot HaRan). This causes a different element dynamic in the personality. It is done in a specific manner, tailor made to suit the needs of what that person must be tested with and what he must accomplish in that given lifetime. In a past lifetime one who rectified the quality of love, might have to come back to rectify fear. The simple lesson of all this is how important it is to take advantage of where one is at any given moment, to use it to its fullest.

[Translation and commentary by Perets Auerbach.]