Musar do Rodzaju 24:2

המושל בכל אשר לו . One can explain this as Abraham being the subject, seeing that Eliezer was a slave the "senior member of his household," i.e. of the מושל, the master. The hidden message here is that if G–d has granted someone great wealth, and that person is a miser, does not perform charitable deeds liberally, he will surround himself with קליפות, negative influences, which will eventually prevent him from המושל בכל אשר לו, from exercising control over what he thought was his. When a person is generous such as Abraham, however, he will enjoy being in charge of all that is his.

The Pardes Rimonim mentions that the "miniature" number is a reference to Chanoch (otherwise known as the angel Mattatron) who is also called נער, and whose function is alluded to in Solomon's Proverbs 22, 6: חנוך לנער על פי דרכו, "educate the lad in the manner appropriate for him. [In his chapter on the definitions of certain words, the author of Pardes Rimonim defines the reason that Mattatron is called נער as being that he performs the duties of a נער. These duties are comprehensive just as the duties of Joshua, who is described as a נער, a senior servant of Moses, or Eliezer, who is described in that fashion although he was the senior servant of Abraham. According to Kabbalists, Mattatron provides the "food" not only for our world but also for the world of the angels. Ed.] When the souls of Jacob and Joseph respectively expanded from the world of אצילות, their origin, the features of Jacob remained engraved on the throne of G–d. This throne is immediately below the region we have called אצילות. Joseph is immediately below his father in the domain of Mattatron whose activities emanate from beneath that "throne." The significance of the throne is the mystery of בריאה, whereas the significance of Mattatron in the same scheme is the mystery surrounding יצירה, [a more advanced state of the creation of matter. Ed]. Concerning this latter aspect of Mattatron's activities, the Torah describes Joseph here as 17 years old, i.e. a "junior." Kabbalists also refer to Mattatron as עבד. The Zohar points that out on Genesis 24, 2 where Abraham instructs עבדו זקן ביתו, "his servant the senior member of his household," to get a wife for Isaac. I have explained this at length in my commentary on חיי שרה. The expression עבד also occurs in Joseph's life when the latter is sold by his brothers. G–d sent His angel along to protect Joseph on his various journeys. This guidance was of a similar nature as that described in Exodus 23, 20: הנה אנכי שולח מלאך לפניך לשמרך בדרך, "Here I am sending an angel ahead of you to protect you on the journey." Our sages identified that angel with the angel Mattatron, as mentioned by Rashi on that verse. [The fact that Rashi mentions that the numerical value of 314=מטטרון=שדי, clearly establishes that Mattatron is active in matters of יצירה, an activity requring the attribute of שדי. Ed.]

Bereshit Rabbah 59,8 describes Eliezer's features as resembling those of his master Abraham, basing itself on the words זקן ביתו, to mean that he resembled his master. The words המושל בכל אשר לו, are interpreted by that Midrash as a compliment that Eliezer held his evil urge in check. The Midrash goes on to interpret the words ויאמר אליו העבד in 24,5 by quoting Hoseah 12,8: "A trader (כנען) who uses false weights, who loves to overreach." "The trader," i.e. כנען, supposedly refers to Eliezer. Probably the Midrash, too, makes a destinction between the instances where the Torah uses the term עבד for Eliezer, and where another term such as זקן ביתו is employed. Whenever the latter term is used, Eliezer had Mattaron hovering over him.