You're Not Supposed To

You’re not supposed to do that. And certainly not that way.
Though no canons or rubrics, there was a time when we had rules about certain things because -- well, that’s the way we have always done it -- we insisted that was the way it was supposed to be done. Who knew or cared whether they were universal in the Church, or just something that had grown up locally. 
Women were not supposed to come to church with head uncovered. Arriving sans hat, God forbid, you must spread a handkerchief over and pin it to your hair.
Arriving at your pew in the nave you were supposed to kneel and say a prayer of private devotion. Even if you arrived during the processional hymn -- which could be quite awkward and odd, putting the kneeler down on the toes of those who were standing and singing.
If you arrived after the Confession of Sin you were not supposed to receive the Sacrament.
You were not supposed to receive the Sacrament more than once in 24 hours.
You were not supposed to chew the communion wafer, but let it melt on your tongue. 
You were not supposed to touch the chalice, but let the minister guide it to your lips and serve you.
Returning to your pew from the Altar rail you were supposed to walk with your hands folded and your head bowed. 
Arriving in your pew from the Altar rail you were supposed to kneel and say a prayer.
After the recessional hymn you were supposed to wait kneeling until the Altar candles were extinguished. 

If there was consecrated Bread or Wine left after the service, Altar Guild must work in silence, because you are not supposed to speak in the presence of the consecrated Sacrament.
Some of the customs probably had pious origin, others perhaps just busybodies. But we like to do things the way they are supposed to be done. Even obsessively. In the Preface to the First Book of Common Prayer (1549), which is reprinted in the 1979 prayer book as a historical document (BCP 866) there is a discussion of the Bible lessons that are to be read in worship. Whether stern chastisement or tongue in cheek, a concluding sentence speaks of our obsession with rules. “Moreover, the number and hardness of the Rules called the Pie, and the manifold changings of the service, was the cause, that to turn the Book only, was so hard and intricate a matter, that many times, there was more business to find out what should be read, than to read it when it was found out.” 
Odd folks we are, when busyness is our business and the rules about what and how to do are more important than the doing of.
TW+