The Basics of Judaism: Jewish Texts: The Beauty of Holiness:
What is the meaning of the "beauty of holiness" in Psalm 110?
The sages interpret Ch.110 of Psalms as written in praise of Abraham.
The phrase "hadrei kodesh" is interpreted in several different ways by
the commentators. Rashbam says it refers to the beauty of Abraham's army when he made war against the four kings (Gen. Ch.14). RaDaK says it refers to the beauty of the holy city of Jerusalem, where Abraham was blessed by Melchizedek after his victory over the kings. Rashi says it refers to Abraham's spiritual beauty when he recognized the greatness of G-d as a small child (and as a result of which he was victorious in his endeavors). The phrasing in this Psalm is very poetical; it doesn't have a simple, "obvious" interpretation.
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