“The kingdom of God is… righteousness, peace and joy in the Holy Spirit.” Romans 14:17 NIV
The nature of religion is so far from consisting in forms of worship or rites and ceremonies that it does not properly consist in any outward actions of any kind. It is true, a person cannot have true religion who is guilty of vicious, immoral actions, or who does to others what he would not they should do unto him if he were in the same circumstances. It is also true that one has no real religion who knows to do good and does it not.
Yet one may both abstain from outward evil and from good and still have no religion. Or two persons may do the same outward work, such as feeding the hungry, or clothing the naked. One of these may be truly religious and the other have no religion at all: For one may act from the love of God, and the other from the love of praise.
Although true religion naturally leads to every good word and work, the real nature of religion lies deeper still, in the hidden man of the heart. I say of the heart, for neither does religion consist in orthodoxy or right opinions. Although these are not properly outward things, they are not in the heart but in understanding. One may have right opinions on every point, even zealously defend them, and still not have any more religion than a pagan. True religion is of the heart.