6. Public worship must be performed in spirit and in truth. Externalism and hypocrisy stand condemned. The forms of public worship have value only when they serve to express the inner reverence of the worshiper and his sincere devotion to the true and living God. And only those whose hearts have been renewed by the Holy Spirit are capable of such reverence and devotion.
7. The Lord Jesus Christ has prescribed no fixed forms for public worship but, in the interest of life and power in worship, has given his church a large measure of liberty in this matter. It may not be forgotten, however, that there is true liberty only where the rules of God's Word are observed and the Spirit of the Lord is, that all things must be done decently and in order, and that God's people should serve him with reverence and in the beauty of holiness. From its beginning to its end a service of public worship should be characterized by that simplicity which is an evidence of sincerity and by that beauty and dignity which are a manifestation of holiness.
8. Public worship differs from private worship in that in public worship God is served by his saints unitedly as his covenant people, the body of Christ. For this reason the covenant children should be present so far as possible as well as adults. For the same reason no favoritism may be shown to any who attend. Nor may any member of the church presume to exalt himself above others as though he were more spiritual, but each shall esteem others better than himself.
9. It behooves God's people not only to come into his presence with a deep sense of awe at the thought of his perfect holiness and their own exceeding sinfulness, but also to enter into his gates with thanksgiving and into his courts with praise for the great salvation which he has so graciously wrought for them through his only begotten Son and applied to them by the Holy Spirit.
(From the Directory for Worship)