Answer:
The subject of the sentence is "you" and the predicate is "believe in a manner that bespeaks the determination with which you believe it."
Step-by-step explanation:
The subject of a sentence is the term that is suffering the action of a verb and that does not have a preposition preceding it. To find out who the subject is, we must use the verb of the sentence and establish a question in relation to that sentence. For example, in the question above, I use the phrase "to say what you believe in a manner that bespeaks the determination with which you believe it", to find out who the subject is, we can ask "to say who believes?", The answer it is "you", so this is the subject.
The predicate of the sentence is everything that is referring to the subject. In this case, we can say that the predicate is "believe in a manner that bespeaks the determination with which you believe it".