1. We trust the Holy Ghost to bring to Christ all those appointed to eternal life.
2. The call to the unbeliever is to become a worshipper of the Triune God.
3. This is a thing foreign to him as an unbeliever.
4. It is therefore to be expected that Christian worship isn't readily "accessible" to him.
5. It will become so as he is converted and instructed.
6. Both actually begin as he observes and participates as he is able.
7. It is therefore necessary that he observes worship done decently and in good order, according to God's revealed standards.