Christianity is like appetite for food. God puts desire for spiritual understanding in each person, who can then recognize the truth that God offers and develop a relationship with Him, or choose to believe a distracting lie instead. Either way they are relieving an appetite for spiritual hunger.
Some people abuse the appetite for food that God designed into people. A small minority of them develop an eating disorder based on denial, meaning that there is something wrong with eating, don’t do it. So they jeopardize their health by losing too much weight. In a free and prosperous country like America, the vast majority of people with an eating disorder take the opposite approach, indulging themselves with the idea that if it feels good, do it. So they jeopardize their health by becoming overweight or even obese. They assume that the ill effects caused by their lifestyle are normal, they are just victims of the times we live in and medical science can provide solutions.
The same is true for spiritual appetite. A small minority of people believe that denying themselves is a way to please God, but instead of developing a relationship with Him to learn what is best, they just look for ways to avoid pleasure or focus on doing chores for Him at the expense of not enjoying the full life that God wants for them. They take a path to hardship by following a simple list of legalistic rules without understanding the more complex points of the relationship. They are like a child that buys the first card they see for mommy instead of making the effort to learn what she likes and showing love by making their own homemade version. The large majority of people with a spiritual disorder in a free country like America choose the other extreme, indulging themselves in carnal ways without understanding their relationship with their Creator. They justify their behavior by limiting their knowledge of Christianity to milk-of-the-Word beliefs like God loves us, accepts us unconditionally and wants us to be happy if we just say we love Jesus. They assume that God is eager to accept their lack of accountability to their relationship with Him.
Looking at this from a Paul vs James perspective, Paul says we can do nothing to please God from our own abilities, it’s all about having faith in the Grace that God freely offers us, (BUT this does not give us an excuse to ignore our accountability to our relationship with Him, Paul also says we are to test ourselves to see if we really are part of His family). James says that if we are part of His family we must show fruits of His Spirit in us as works or our faith is dead. So we prove our faith by showing that we live by the practical good examples James describes.
So while driving down the road of life, spiritually obese people end up in the “It’s all Grace” ditch because they think that Christianity is about God wanting us to be happy and extending Grace and forgiveness to us no matter how we live, and self-denying people end up in the “Do the works” ditch because they think their sacrifices are a way to please God and earn his favor. Fulfilling a spiritual appetite is about recognizing and avoiding both ditches.
People that understand that their Creator wants to have a relationship with them (which includes guiding them into a more truthful way of living) know that they must set aside their desire to be in charge of everything about their lives. They must choose to let God be in charge so they can gain wisdom from the guidance He offers and bond together with Him more and more. So like any other relationship there are behaviors to learn to make it work (except that it is not an equal partnership, we are submitting to His authority over us). It’s not about looking for rules to follow, it is seeing how our desire to learn how to please Him is evidence that we love Him and that the relationship is working.