"Are we required to follow what is modeled?"
"Why wouldn't we want to follow what is modeled?"
New Testament church practices are wide ranging. Much is modeled for us. Because of this, we need to ask and answer the above two questions about practices individually as opposed to a whole. It does little good to answer "Yes" or "No" to a question such as, "Should we follow what we see in the NT?" That question is too broad. Rather, we do well to look at specifics.
The first of the two above questions has to do with what God requires of us. In other words, is it an issue of obedience? Are we sinning if we fail to follow what we see? It can often be difficult to determine the answer to this one.
The second question relates to our own motivations. If we choose to not follow what is modeled for us, why do we do so? What is our reasoning? This appears to be less an issue of obedience than desire.
Let's look at a couple of examples to tease this out. For our purposes we'll look first at the Lord's Supper. First question: are we required to celebrate the Lord's Supper as we see it in the NT? I believe the answer is a mixed one. There are certain things that we do have to do. For example, Paul makes it clear in I Corinthians 11 that we should wait for everyone to arrive prior to eating. We should also eat in an orderly fashion. However, there does not seem to be a command for us to treat the Lord's Supper as a full meal.
Second question: why wouldn't we want to follow the model of the Lord's Supper as set forth in the NT? If we choose, for example, not to have the supper be a full meal, what is our motivation? What causes us to choose to deviate from the model we see in scripture?
Let's take another example: church gatherings. First, are we required to gather as the early church generally did? Specifically, do we have to meet in homes? Also, do we have to meet in a participatory fashion? Further, must we meet for the purpose of mutual edification? As I look in scripture, I see no indication that the church is required to gather in houses. For example, we know that Paul met quite a few times with other believers in the Hall of Tyrannus. As for meetings, no outright command exists that they be participatory. I'll admit that the language in I Corinthians 14:26 can be interpreted in various ways on this issue; however, I don't believe it is a clear command. What about mutual edification? This is commanded. I Corinthians 14:26 and Hebrews 10:24-25 make this clear.
Second question(s): why wouldn't we want to gather in homes? Why wouldn't we want to meet in a participatory manner? What is the motivation behind deviating from the NT model? Many churches do not meet in homes. Many do not meet in a way that allows mutual participation (at least in worship services). What, then, is the motivation behind these decisions?
These two related questions can be uncomfortable for all of us. The reason is that they may point out either disobedience or poor motivations on our part. No one that I know enjoys being informed that they are wrong about something.
However, if we are unwilling to ask these questions, it shows something else. What's that? It shows that we are either afraid that our practices are unbiblical or that we don't care if they are. Both of those are extremely problematic.
My encouragement to you is to dare to ask these two related questions. They may not be welcomed by your friends and family, but it will still be worth the effort.