The Apostle Paul is telling Timothy that spiritual fitness is much more profitable for all things, because we have the promise of the life that now is and of that which is to come. The goal of spiritual fitness, according to scripture, must be godliness. Let’s start with biblical fundamentals. You must begin with a new birth. Admitting that you are a sinner, turning to Jesus by faith alone, believing that He paid the price for your sin in full, and accept the free gift of salvation, which will make you a New Creation. We still retain our old nature, but no longer are we under its control.