The full sentence, with the implied part added, is this:
"It is also imperative to respect different beliefs, making sure [that] every interest and faith is suitably represented at all times."
By adding the implied part ("that"), we flush out the subordinate clause embedded in the participial modifying clause. Let's pretend the subordinate clause is a main clause and write this:
"Every interest and faith is suitably represented at all times."
The subject is compound -- "interest" and "faith." A compound subject whose parts are joined by "and" usually takes a plural verb regardless of whether those parts are plural or singular. That's clear. Some compound subjects, however, take singular verbs, such as -- "Two and two equals four" and "Peanut butter and jelly makes a great sandwich."
"Interest and faith" as a compound subject, however, is not like these compounds in that it is not usually spoken of as a single unit or single unit of meaning (like "peanut butter and jelly"). Each part ("interest" and "faith") has a distinct and different meaning and is additive.
Finally, "every" in "every interest and faith" might lead one astray, suggesting a singular verb, as we find in “Every man and woman deserves justice.” That is, “ALL deserve justice,” and so the singular verb. “Man and woman” in this sentence is actually a unitary compound subject masquerading as a plural subject.
For these reasons, I think the sentence should probably read:
"It is also imperative to respect different beliefs, making sure all interests and faiths are suitably represented at all times."
Hope this helps.