Several of the ideas mentioned above are expressed in the following passages from the Zohar. The following selections are from Zohar vol. II 94a-99b.The protagonist is an old man (Saba), ostensibly a donkey-driver, who meets Rabbi Yose, one of the sages of Rabbi Shimon bar Yochai's circle, on his travels. The donkey driver poses several questions to Rabbi Yose, who fails to appreciate their true significance. However, his wiser colleague, Rabbi Chiya, senses that there is more to the questions than meets the eye, and after probing the matter, they realize that the old man is in fact teaching them some of the deepest secrets of gilgul…Along the way, the Zohar also deals with such questions as, "Why do some people never marry?", "What happens to the soul of a person who dies without having children?", "Why do innocent children die young?"

One night, Rabbi Chiya and Rabbi Yose arrived simultaneously in Migdal Tzur. They both planned to lodge the night there and were delighted to see each other.

Rabbi Yose said, "You don't know how happy I am to behold the countenance of the Shechina!"

He was referring to Rabbi Chiya whom he met there unexpectedly. Rabbi Yose referred to Rabbi Chiya as "the countenance of the Shechina" because the Shechina rested upon him constantly. (Damesek Eliezer. Cf. Zohar II, 38a)

What is the snake that flies through the air and goes about all alone?

For while I was traveling, I was bothered by an old man, a donkey-driver, who plied me with questions the entire way! The first question he asked me was, "What is the snake that flies through the air and goes about all alone, with an ant resting between its teeth?" He began with union and ended with separation!

As explained in Or Hachamah the meaning behind this question is as follows: What is the lot of a person who did not fulfill the mitzvah "to be fruitful and multiply," and did not even marry so that he might have children? When his soul ascends on High, it flutters about in the air ("flies through the air") and cannot settle. It does not find a partner; it "goes about alone" and unproductive, like a snake in this world. For all animals go about in pairs, other than the snake, which travels by itself. (See Bereishit Rabba chap. 98, par. 11) When this soul descends again into a body, it does not find a mate, and remains alone. 'With an ant resting between its teeth.''Ant' refers to the soul-mate of that man - she is lost to him now because he had refused to marry her and fulfill the mitzvah of having children. While he undergoes gilgul the "ant"1 - his designated wife - 'rests between his teeth,' for he constantly thinks about her, grinding his teeth in anger at himself for not having married her when he had the opportunity. She, however, finds solace in the other man she marries. Thus 'he began with union and ended with separation' - before his soul descended into a body for the first time, his soul-mate was announced - 'he began with union,' of his soul and that of his designated soul-mate. This time, before his soul descended for a second time, no announcement was made - 'he ended with separation,' as half a person, since he descended without his soul-mate. (See Bamidbar Rabba 3:4)

Two are one, and one is three…

The old donkey-driver's second question:

"And what is the eagle that makes her nest in a tree that never was? Her children were stolen away but not as created beings, for they were created in a place where there is no creation. When they ascend they descend, and when they descend they ascend. Two are one, and one is three."

Behind this question lies the mystical interpretation of the commandment of yibum, the levirate marriage. If a man dies without having any children, then his brother (called the yavam) is obligated by Torah to marry this deceased brother's widow (the yevama).He perpetuates, thereby, the name of his deceased brother (see Deut. 25:5ff.). The eagle here alludes to the yevama who, after the death of her husband, must "make her nest" (marry) in "a tree that never was" - a man (compared to a tree in Deut. 20:19) who was not intended for her (i.e. her yavam). [In fact, had the woman's husband divorced her, she would be forbidden to any of his brothers during his lifetime.] "Her children were stolen away" refers to the children she could theoretically have had with her first husband who died, and whose soul now enters the child she will have with the yavam, as will be explained below.

But the children she could have borne are not created beings that were stolen from her, having never actually been born ("but not as created beings for they were created in a place where there is no creation." Or HaChamah) "When they ascend" - when the souls of people who die without leaving children ascend from the bodies they occupied (Zohar Harakiah); alternatively, when the yavam and the yevama (the brother and former wife) ascend to become the parents of the deceased (when he is reincarnated as their child), then the soul of the deceased descends into their child. By fulfilling the commandment of yibum and allowing the deceased's soul to descend into a body ("when they descend") in order to perpetuate his name, the yavam and yevama are themselves raised to a higher spiritual level ("they ascend"). Thus, "two are one" - the deceased and the newborn are one soul; "and one is three" - the newborn is endowed with three souls: one from the deceased, another from the yavam and a third from the Holy One Blessed Be He (Or Hachamah; Mikdash Melech)

The Arizal explains that there is a distinct advantage in yibum over regular gilgul. Namely, a child born to a yavam and yevama can acquire all three levels of soul - Nefesh, Ruach and Neshama in a single lifetime.

...a pure and unsullied Neshama (the maiden) that has merited to ascend to Gan Eden

The old donkey-driver's third question:

"Who is the beautiful maiden without eyes, whose body is concealed and revealed, who comes out in the morning and disappears during the day, who is adorned with ornaments that never were?"

This refers to a pure and unsullied Neshama (the maiden) that has merited to ascend to Gan Eden as a result of its good deeds (and therefore it is called "beautiful"). "Without eyes" - the Neshama cannot be seen. However, the Neshama is clothed in the lower level of Ruach, which is called its "body" when compared with the Neshama. This level of Ruach is "concealed" (it is not a physical body) and revealed (compared with the even more concealed Neshama it is regarded as revealed). "It comes out in the morning" because after midnight, towards morning, the Holy One, Blessed Be He, descends with all the souls of tzadikim from the upper aspect of Gan Eden.

[Note:The Zohar explains elsewhere that there are in general two levels of Gan Eden - Gan Eden haElyon (the higher Garden of Eden) and Gan Eden haTachton (the lower Garden of Eden). The difference between them is that the aspect of G‑dliness revealed in Gan Eden haTachton is from the supernal midot, whereas the aspect of G‑dliness revealed in Gan Eden haElyon is from the supernal mochin, a far greater illumination. Furthermore, the souls in Gan Eden haTachton experience the revelation of G‑dliness as the emotional revelation of consummate love and awe, whereas the souls in Gan Eden haElyon experience the revelation of G‑dliness as profound and inspirational insight into Divine Truth.]

It is then that the neshamot from the upper aspect of Gan Eden clothe themselves in their "bodies" (i.e., Ruach, which is called its "body" as mentioned above). But when day breaks, the Holy One returns to the upper aspect of Gan Eden and the neshamot go with Him. Accordingly as is said in Or HaChamah, the Neshama "disappears during the day." The Neshama "is adorned with ornaments that never were" - with the souls of tzadikim, some of whom are new souls that have never descended into a physical body, thus "they never were." (Damesek Eliezer)

Although it is not clear that the Arizal is talking about this paragraph of the Zohar,the Arizal explains in Sha'ar HaGilgulim, introduction 3, that after a person has rectified his level of Nefesh, he normally must die and be reincarnated in order to begin rectifying his Ruach. However, occasionally, if a person has the correct intentions when he goes to sleep at night, as he places his soul in the hands of G‑d (as in the liturgy of the Bedtime Shema: "in Your hands I deposit my soul") that his Nefesh will remain above and only his Ruach will descend when he awakes in the morning. Thus, it is as if he comes into another gilgul in a different body. Once he has perfected the level of Ruach, then the Nefesh can return to the body it was enclothed in originally, so that the Ruach will become clothed in the Nefesh. Subsequently, if he has perfected his Ruach as well, the same process may be repeated. His Nefesh and Ruach ascend while he is asleep and remain above. When he wakes up in the morning, only the Neshama will descend. If he succeeds in rectifying the Neshama as well, then the Ruach and Nefesh will descend into the same body. The Nefesh will become the vehicle for his Ruach, and his Ruach for the Neshama, and he will no longer be required to return in gilgul.

Rabbi Yose continues to tell Rabbi Chiya about the strange old man he had met:

All these questions he asked me on the way, and it distressed me. But now I can relax. Had we been together, we would have occupied ourselves with Torah discussions, instead of other nonsensical matters!" This old man… Do you know anything about him?

Rabbi Chiya asked,"This old man… Do you know anything about him?" He replied, "This I know: his chatter is worthless, for had he known anything he would have begun discussing Torah, and the journey would not have been wasted!"

Rabbi Chiya said, "Is the donkey-driver here? Sometimes those apparently empty-headed fellows can turn out to be a golden bell." "Here he is, preparing food for his donkey." They called him over and he came before them. He said to them, "Now two are three and three are as one!"

The two of them, Rabbi Yose and the donkey-driver, had now become a group of three - together with Rabbi Chiya. And all three were united ("as one") in their common quest to learn Torah. (Zohar HaRaKiah)

But Rabbi Yose [still did not grasp the true nature of the old man's comments, and he] said to Rabbi Chiya, "Didn't I tell you that all of his words are meaningless and idle chatter?"

The old man sat down before them and said, "Rabbis! Only recently I became a donkey-driver. I was not always a donkey-driver. But I have one young son whom I send to school. I want him to occupy himself with Torah, and so when I meet a rabbi on my travels, I try to act as his donkey-driver. Today I thought I would hear some novel Torah insights, but I heard nothing!"

I was not always a donkey-driver…

The assumption is that it was he who tried to learn Torah from the rabbi. However, as we will see shortly, the donkey driver intended to teach the rabbi secrets of the Torah!

Rabbi Yitzchak Luria (Kehillat Yaakov; Mikdash Melech) comments on the above piece: Know that the souls of other tzadikim descend from that world [higher world] to reveal secrets of the Torah to the righteous and very pious. This is the esoteric explanation of the Mishna: "All those who occupy themselves with Torah for its own sake are worthy of many things…. They reveal the secrets of the Torah to him…" (Ethics of the Fathers 6:1). Understand that it does not state, "the secrets of Torah are revealed to him," but rather, "they reveal [the secrets of the Torah] to him" - via the souls of other tzadikim. Now the manner in which the tzadik's soul is revealed to a person in order to divulge to him Torah secrets, is this: There is no Neshama that does not have a levush (garment) called its cloak or its rabbinical attire [in the case of a scholar]. This garment is woven from mitzvot [that a person fulfills]. Just as the angels who appeared to Abraham came clothed in a body, so too the souls of tzadikim clothe themselves in a rabbinical garment and appear to a person in order to teach him secrets of the Torah.

[Depending on the level the recipient has reached, the tzadik's Neshama from Beriya, or his Ruach from Yetzira, or his Nefesh from Asiya, will reveal the secrets of Torah to the person who comes from his soul-root].

When only the level of Nefesh of the tzadik becomes clothed [in a garment], then it is revealed as a donkey-driver…. Know, however, that it is impossible for the soul of any tzadik to clothe itself in that rabbinical garment unless a spark of Moses, our master, clothes itself in his soul.

Rabbi Yose said, "Of all the things I heard you say, only one of them surprised me. You either said it out of foolishness or because you did not know what you were talking about." "And what was that?" asked the old man. "About the beautiful maiden, etc." The old man began, "The Lord is with me, I do not fear - what can man do to me? I am not afraid to reveal the secrets of the Torah! (Zohar HaRakiah; Mikdash Melech) The Lord is with me, to help me… It is better to rely on the Lord…" (Psalms 118:6-8). How good and pleasant, cherished and lofty are the words of Torah. The four expressions used here correspond to the four levels of Torah interpretation, called "PaRDeS".2 How shall I proclaim them in front of Rabbis, when I have not heard a single word of Torah from their mouths?

[Since Rabbi Yose assumed that the donkey-driver was simply a foolish old man, he reviewed his studies to himself, in silence.]

As a result, I am not able to judge whether they are indeed worthy of learning secrets of the Torah. Alternatively, the old man said this out of humility. Since the verse states, "do not stand in the place of great men" (Proverbs 25:6) he was reluctant to speak at all, until the rabbis had spoken first. However, since they had not spoken, and he was about to utter words of Torah, he had nothing to be ashamed of: As far as I am concerned, I must say that I am not ashamed to say words of Torah before all (Rabbi Chaim Vital in Zohar HaRakiah; Mikdash Melech).

From this point on, the attitude of Rabbi Yose changes, as he listens to the words of the old man who begins to reveal secrets of the Torah.

[Translation and commentary by Moshe Miller]