In my article Biblical Formatting I have indicated that the Biblical Author will use a theme-detail-theme style to indicate a paragraph the same way a modern author will use indentation and a line of white space to indicate a paragraph. The fact that several sentence form one paragraph generally indicates exegesis: The diverse sentences are perceived as indicating one central theme; they are not interpreted exclusively.

With this in mind let us review verses Lv21-18:21 which is written in a theme-detail-theme style as shown below. The verse-paragraph discusses the prohibition of a blemished priest serving in the Temple.
• Theme: For whatsoever man he be that hath a blemish, he shall not approach:
• Details:
  • a blind man,
  • or a lame,
  • or nose-crushed,
  • or limb asymmetry,
  • or a man that is broken-footed,
  • or broken-handed,
  • or long-eyelashed,
  • or eye-marred,
  • or that hath his eye overspread,
  • or is scabbed,
  • or scurvy,
  • or hath his stones crushed;
• General: no man of the seed of Aaron the priest, that hath a blemish, shall come nigh to offer the offerings of HaShem made by fire; he hath a blemish in him; he shall not come nigh to offer the bread of his G-d.

The Rashi comment follows the above theme-detail-theme structure:
• No blemished priest may serve
• for example, blind, broken-limbed, lame
• or any blemish.
Rashi's basic idea is to infer that any and all blemishes invalidate a Priest from serving. Here because the diverse Biblical verses form one paragraph Rashi is justified in seeing the paragraph,
• Not as listing an exclusive list of separate blemishes so that only those blemishes would invalidate a priest from serving in the Temple
• but rather, as listing a general theme, (along with accompanying examples,) of prohibiting priests with any blemish from serving.
In other words the paragraph structure encourages the reader to see the paragraph examples, not as exclusive, but as examples of the general-theme statements that no blemished-priest may serve.

Advanced Rashi: Notice how Rashi simply generalizes: Any blemish. Those who are familiar with the theme-detail-theme method know that typically, Rashi will give Criteria of generalization. In this particular case he doesn't. However a beautiful and masterful analysis provided by the Sifrah and Malbim delineate categories of blemish and provide the necessary analysis. The categories of blemish are:
• Organ blemishes: Such as lame, blind, broken-armed
• Whole-person blemishes: Such as discolored skin, dwarfs, giants
• Non-visible blemishes in function: Such as drunk, imbeciles
• Blemishes of the past: such as cesarian birth
The examples in the verse-paragraph above only prohibit organ blemishes. The final law is that A priest may not serve if he has permanant organ-blemishes, whole-person blemishes, or non-visible blemishes in function but may serve if he has past-blemishes. In making this derivation the Sifrah and Malbim were encouraged by both logic and textual nuances. As a simple example of textual nuances supporting the above distinctions, note that verse above explicitly states the priest may not serve if a blemish is in him, thereby emphasizing that only actual present blemishes invalidate the priest, not blemishes of the past.

Sermonic points: There are some obvious sermonic points here.
• A person is judged by his present not by his past
• A person is judged both by what is visible and by non-visible limitations in his capacity.