Milliners and tailors get the advantage of the first three-quarters of an hour.

The "preliminaries" are the time to scrutinize the fresco, and look round to see who is there, and get yourself generally fixed.
This idea is fostered by home elocutionary professors who would have the minister take the earlier exercises of the occasion to get his voice in tune.

You must not speak out at first.

It is to be a private interview between you and heaven.

The people will listen to the low grumble, and think it must be very good if they could only hear it.