Avoid scrupulously the propagation of any particular set of views in politics, art, history, philosophy, or theology. "Tros Tyriusque mihi nullo discrimine agetur" [Trojans and Tyrians will be treated by me without distinction] are words which Virgil puts into the mouth of Queen Dido. The North American Review has adopted them as its motto. The promise they contain is one that should be kept by the librarian also.
The librarian who uses his position to make proselytes prostitutes his calling. State the mental tendencies and the characteristics of disputants, but do not become their advocates.
If a reader, asks you for your own views regarding some matter about which there is controversy, give them to him if you choose. Decline to give them if you choose. Remind him, however, in either case, that if he wishes to have an opinion of his own, he must study the subject in its different aspects and form one for himself. Say gently to immature persons that they can not expect to have opinions upon profound controverted questions, and that they must wait until they grow in knowledge, and until their reasoning powers develop, before their views on such matters will be of value.
Collection development in the church library should strive for balance. Although you may not carry works that contradict your church's doctrines you may need works that helps readers understand other viewpoints. The wise church librarian will be on the alert to his or her own biases (whether it's a fondness for cowboy stories or conviction about Arminiansm) when selecting material.
Avoid religiously the practice of cramming the minds of young inquirers with one-sided views in regard to questions in dispute.