It would simply be "They respect each other".
Respect in time tenses is either spelled, "Respected", "Respect", or "Will Respect."
The fact that it's third person does not change the word since it can be said as "I respect you", "You respect yourself" "They respect each other"
They were very strict against Catholicism because of Christian faith
An infinitive is the infinitive form of the verb that is being formed with "to" plus the base form of the verb. It can be used either as a noun, adjective or as an adverb. ... This infinitive functions in the sentence as an adverb, modifying the verb "create".