The letter yud which differentiates between these two letters is appended behind the letter daled.
Though yud is the smallest of all the letters, it is the head of them all, in the sense that [the writing of] each letter begins with it.
Indeed, "The World to Come was created with the letter yud."
This concept is alluded to in the phrase, -- "For all that is in heaven and on earth [is Yours]."
The Aramaic translation [of the word kol ("all"), cited in the Zohar] means "united in heaven and earth."
This refers to the Sefirah of Yesod through which Malchus receives the flow of Divine light.
The next word in the verse, shmayim ("heaven"), comprises two elements -- esh ("fire") and mayim ("water").
Fire stands for the attribute of Gevurah ("severity") and water for the attribute of Chesed ("lovingkindness").
[These two attributes in turn serve as the source of all the other Divine emotive attributes.]
The final word, eretz ("earth"), stands for the attribute of Malchus.
The verse thus teaches that by means of the Sefirah of Yesod, Chesed and Gevurah unite with Malchus.
[Evil, however, lacks this quality; as implied by the verse,] -- "And the poor man had nothing" [lit., "...lacked all"].
[The word rash ("poor man") is related to the letter reish, and the word kol ("all") is related to the above-mentioned Sefirah of Yesod, which in turn is related to the letter yud.]
The verse can thus be understood to mean that the letter reish lacks [the unity alluded to in the verse that speaks of] "all in heaven and on earth," since it lacks the attribute of Yesod that brings about the above-described union [of the attributes that are represented by heaven and earth].
This situation leads to the concealment of the power of speech, [which is a metaphor for the spiritual energy emitted by the Sefirah of Malchus].
This is hinted at in the verse that begins, -- "I was dumb with silence, I held my peace."
The Divine power of speech is thus silenced because the light and life-force that animates the forces of evil is merely a reflection of a ray from a Divine source which is (so to speak) outward [i.e., "reluctant"].
[This concealment allows for the existence of evil.]
[The contrast between the unity that is generated by holiness and the fragmentation that characterizes evil is highlighted when one compares the way in which Yaakov and Eisav each described their wealth.]
Yaakov said, yesh li kol -- "I have all"; Eisav said, yesh li rav --"I have much."
Holiness, which is personified by Yaakov, has kol, the element that "unites heaven and earth."
The forces of evil, which are embodied in Eisav, lack the uniting element of kol; instead, they have rav -- "much", implying a multiplicity of physical blessings.
Explaining this concept further, the Zohar cites a teaching of the Master of the Heavenly Academy:
"He who is small is great, and he who is great is small."
For that which is holy is "small" in the sense that it possesses the capacity for self-diminishment.
In this spirit it is written, -- "How shall Yaakov stand? -- For he is small."
Nevertheless he is "great", in the sense that the unifying element of kol is revealed within him.
By contrast, he who describes himself as having rav --i.e., as being great, as a man characterized by multiplicity -- is "small".
Of him it may be said, l'rosh ein kol -- "The poor man [in this context: `the evil man'] lacks all (kol)."
Being unable to benefit from the unifying quality of kol, the only blessings he enjoys are physical ones.
[The latter conception of poverty reappears in the interpretation of the Zohar on the phrase,] -- "Young lions are in need, and go hungry."
[Utilizing the similarity between kefirim ("young lions") and parim ("bulls"),] the Zohar understands this verse as alluding to the seventy bulls that were sacrificed in the Beis HaMikdash during Sukkos.
Like the seventy patron angels of the nations that they represent, the number of these bulls diminished daily.
Being blessed with nothing richer than material bounty, they are described as being "in need," and "poor".
Speaking likewise of these seventy bulls, the [Kabbalistic text entitled] Mikdash Melech understands them to be referring to the forces of evil.
Both interpretations are valid.
Since the spiritual life-force that animates them is merely a reflection of a ray from a (so to speak) outward radiation of Divinity, it is invested in them in an exceedingly tenuous manner.
This very obscuring of the spiritual life-force in turn increases their gross self-assertiveness.
Pharaoh, for example, boasted, "The Nile is mine, and I made it."
This claim is the very opposite of the truth.
[Pharaoh made this statement because the river used to rise at his approach.
In fact, however,] this phenomenon resulted from the blessing that Yaakov gave him (as Rashi notes in his comment on the verse, -- "And Yaakov blessed Pharaoh").
In fact, Pharaoh's very name hints at his stiffnecked insensitivity to G-dliness.
For the letters that constitute the name Pharaoh can be rearranged to spell he'eref ("the back of the neck"), which is a metaphor for stubbornness.
In boasting that "the Nile is mine," he was thus ungrateful enough to deny [the source of his blessings]. The life-giving influence that he received from Above served only to bloat his ego.
The chapter continues to explain that the yud appended at the back of the daled signifies the unifying element that is known as kol, as in the verse, kol yesh li (lit., "I have all").
This element is lacking in the spiritually poor man who is described as rash a word that is cognate with the name of the letter reish.
When the forces of evil claim, yesh li rav (lit., "I have much") -- signifying a multiplicity of blessings, though merely material ones -- this merely increases their self-centeredness.