Sectarianism is so deep-rooted in certain individuals that anything coming from their opponents they would automatically reject. In-fact, rejecting without any level of evaluation simply because it is emanating from the opponent is itself a sign of suffering from deep sectarianism.
Many years ago as a student of theology I found myself inadvertently amongst those whom my teachers have advised me as astray and should avoid. However, it has always been my nature to hear both sides of contention before making judgements. So I made good use of the opportunity and interrogated them. And judging from their answers I found that the difference is almost negligible. I was gifted a book at the end of the dialogue which was written by the founder of this sect. I found that the subject within the book hardly differs much with my teachers’ views.
So I played an experiment; I photocopied the book without the reference to the authors name, and asked my teachers and senior colleagues to review my latest reading material. To those who I presented the original, they rebuked me as soon as they read the name of the author for even thinking of reading such filth. To those who I presented the copy, they praised it as a well written book, though they respectfully said they disagreed slightly on the subject.
This little experiment made me become more alert to any of my own biases and sectarianism that I may be subconsciously guilty of.