When you sit in the average congregation (especially if the church has more than 100 people) you might feel hidden in the crowd. But let me assure you that this is a false assumption. In most church auditoriums (auditoria?) each individual member can be clearly seen by whoever is occupying the pulpit. So if you're a nose picker or a head nodder or an addicted whisperer, your pastor knows all about it.
There are exceptions, of course. Our auditorium here in Long Beach arranges its lighting as though interrogating a suspect behind the pulpit. Congregation members are in the shadow land and the preacher is in the spotlight. In this case I can vouch for the fact that this does not mean our church has adopted the unfortunate posture of audience and performer. We know that God is the only "audience" and all of us are participating in worship.
I recently filled the pulpit in Westminster OPC, Westminster, California. I enjoy ministering in this congregation because they are very receptive. While I am speaking I can see each member sitting very still and giving me complete attention. The body language is quite clear. I attribute this to the fact that they are used to listening to a very good preacher, and they have become "eloquent" listeners.
Now I realize that there are those who are well practiced at appearing to be paying attention although their minds are far from the present scene. But he is an exception, and body language sometimes even gives this away. If some bit of unintended humor comes across the pulpit and the congregation chuckles with me, the zombie dude is still staring into space.
In the Carson Church we had an old duffer (hey! I resemble that remark.) who routinely fell asleep sometime during my sermon. If I didn't finish before noon, his watch alarm would rhythmically beep until someone shook him (never happened) or the technology simply fatigued.
I've seen mothers pace the rear of the auditorium with a whimpering baby on the shoulder, just because she was a faithful saint who wanted to hear something edifying. Then there are the preteen boys who are looking through the Bible for funny stuff. Actually I think that went out when our churches began using versions other than the King James.
I'll never forget the experience I had in the pulpit of our Wilmington, Delaware, church. I had the joy of an enthusiastic German listener (somehow he never actually became a member) who might be expected to cry out "Amen!" on any given Sunday. Rudolph would get antsy on the edge of his pew, and when a crescendo of the message was delivered, he would respond with a lusty "Amen." But on the particular Sunday I have in mind, Rudolph was mounting a peak of excitement when I happened to glance to the other side of the auditorium. There I saw one of our cooler members, leaning on the side of his pew, checking his watch. It was at the same high point of the message! Right then and there I learned that although there certainly are some preachers more eloquent than others, there are also some listeners who are more eloquent than others.
By the way, if you think your preacher needs to learn more eloquence, why don't you pray for him. Ask God to make him so excited about what he has found in the text that all of that joy and excitement will come across the pulpit next week.
And start practicing eloquent listening.