。
Only the brave deserve respect.
Literal
Brave-person [only-のみ] [subject-が] respect [target-に] be-worthy-of.
のみ is a formal/literary restriction particle meaning 'only' — more elevated than だけ. 値する (あたいする) means 'to be worth, to deserve,' taking に for what something is worthy of. The sentence has a classical, aphoristic quality.