Letter 16 of the Screwtape Letters by CS Lewis (page 81 in my book) is a small chapter entirely dedicated to the topic of church attendance and how it Satan can use it to undermine faith, hope, and love. In the beginning of the letter, Screwtape offers this advice to Wormwood:
"Surely you know that if a man can’t be cured of churchgoing, the next best thing is to send him all over the neighborhood looking for the church that ‘suits’ him until he becomes a taster or connoisseur of churches.
"The reasons are obvious. In the first place the parochial organization should always be attacked, because, begin a unity of place and not of likings, it brings people of different classes and psychology together in the kind of
unity the Enemy desires. The congregational principle, on the other hand, makes each church into a kind of club, and finally, if all goes well, into a coterie or faction. In the second place,
the search for a 'suitable' church makes the man a critic where the Enemy wants him to be a pupil. What He wants for the layman in church is an attitude which may, indeed, be critical in the sense of rejecting what is false or unhelpful, but which is wholly uncritical in the sense that it does not appraise--does not waste time in thinking about what it rejects, but lays itself
open in uncommenting, humble receptivity to any nourishment that is going. This attitude, especially during sermons, creates the condition most hostile to our whole policy, in which platitudes can become really audible to a human soul. There is hardly any sermon, or any book, which may not be dangerous to us if it is received in this temper. So pray bestir yourself and send this fool the round of the neighbouring churches as soon as possible."
So, Screwtape’s dislike for churches are because of their potentional to be places of unity and learning.
Churches bring together people of many different cultures, socioeconomic backgrounds, and ways of thinking. Churches, by their very nature, are communal and inviting. Evil, by its nature, is divisive and excluding. To combat the benefit of unity, Screwtape suggests that people be tempted to understand their churches to be more like clubs, where only particular kinds of people can belong. If our Sunday worship is approached in this way, it will inevitably lead to the division that the adversary desires. We should go to church (and throughout our daily lives really) welcoming to others and receptive to the Lord's tutoring. As we interact with the people of different opinions at work, online, and in our schools and neighborhoods, we will be allowing the Lord will to teach us how to feel as he feels, and love and he loves.
"By this shall all men know that ye are my disciples, if ye have love one to another." - John 13:35
Screwtape also despises churches is because they are places of learning—especially learning about his “enemy,” God. Growing in wisdom, knowledge, and understanding leads us deeper into humility and, therefore, closer to the God. The way to stop such education, according to Screwtape, is to tempt human beings to search for a “suitable” church. As a side note, reading that part made me feel very grateful for inspirational way the LDS church is organized geographically. When we've traveled abroad, as soon as we had our address, we knew which ward and stake we belong to. It's already decided. Imagine - if we were to go to each ward trying to decide if we liked it and if it was suitable to us, that would quickly destroy the unity needed in Christ's church. Plus, if we were to choose by ourselves which ward to join, it would likely be one that we don't find challenging and whose membership contains similar people, right? We'd become critics instead of pupils. So I loved that part and think it's a good litmus test for our own hearts: are we going to church as pupils or critics? Sadly, you don't need to go far on the internet to find that Satan is having success in dividing the church and the members in it as they criticize the LDS Church and it's leaders. Rarely will the devil's attempts appear blatantly evil or divisive. The adversary is far too smart for that. Instead, it will appear innocent, maybe even spiritual. It might even appear as an important need within the Church. But, once people’s pride gets involved, division will manifest itself. Every Christian and Saint should be diligent in praying for unity in the Church.
So, after finding the “suitable” church, Screwtape suggests that humans be tempted to join a particular faction or “party” within the parish. He writes, “If your patient can’t be kept out of the Church, [then] he ought at least to be violently attached to some party within it.” And, where there are various parties, there are numerous divisions. Lewis' insights invite us to look at our own criticalness. Do we spend the church service judging the people around us? Do we leave Church only to criticize the lessons, the teachers, the music, people’s clothing, couples’ parenting, etc.? Have we missed an opportunity to learn because we were too busy critiquing? Lewis reminds us that Church is about unity within diversity, solidarity through acceptance, learning through humility, all leading to our greatest hope - that of becoming like our Savior and receiving eternal life through his merits and mercy and grace.
"Wherefore, how great the importance to make these things known unto the inhabitants of the earth, that they may know that there is no flesh that can dwell in the presence of God, save it be through the merits, and mercy, and grace of the Holy Messiah, who layeth down his life according to the flesh, and taketh it again by the power of the Spirit, that he may bring to pass the resurrection of the dead, being the first that should rise."