> Whereas I think what Joona was getting at here was that in "Be not sad", it's split up as "be" and "not sad", rather than "be not" and "sad".

Is it? It can be legitimately thought of either way, and the natural rules of English cause the latter to take the same form as it does for all other verbs. My point holds: negating the verb is done the same way as for all other verbs.

If you doubt this, consider the double negative, "be not not sad." Though a double negative, it's legitimate English; one not goes with the verb, one goes with the adjective. (Most double negatives *are* incorrect, though, as in, "I didn't get no money," where the intention is a single negative.)

Also consider that, where "spurn not compassion" has the negation on "spurn," "spurn no compassion" has it on "compassion." It's "no" instead of "not" because "compassion" is a noun, but the point is that the sentence structure has not changed.