Apostle Paul is at typical example of a true soldier of Christ. He didn’t just do what God expected of him but he also raised other men to do likewise. There are three things a soldier must pay attention to and the things are: fight the good fight, finish the assignment, and keep the faith (2 Timothy 4:7)
Every true soldier must endure hardness in order to fulfill the three things listed above. The prerequisite of enduring hardness are unbendable focus and robust spirituality (1 Corinthians 9:23-27). The hardness requirement is different for different people, you might need hardness against lust of the flesh and another person needs hardness against anger. Whichever, ask the lord for help and you will receive grace to endure hardness.
Prayer line: O lord, I need help! Grant me grace to endure hardness in Jesus name. Amen