Godliness Profitable
1Tim 4:8 For bodily exercise profits a little, but godliness is profitable for all things, having promise of the life that now is and of that which is to come.
While everyone knows that there is benefit in physical exercise and eating right, the flesh is generally opposed to such things, being naturally lazy and pleasure seeking, and as such it requires discipline to carry these out.
Godliness is also a matter of exercise - and the benefits being much greater than physical exercise. But again the flesh resists such exercise and as such one much make an intentional effort and plan to discipline oneself unto godliness.
And as we can see from the context, the actual discipline unto godliness requires diligent application-oriented study of the Bible.
The promise of godliness is not just for the life to come, but even in this life one benefits from godly living.