Thomas A Kempis 1.25 - The earnest amendment of our whole life

Be vigilant and diligent in God’s service, and spend some time considering what drew you to the spiritual life rather than the worldly one. Wasn't it a desire to live for God and become more spiritual? So be eager to improve, because you will receive your reward soon enough, and neither fear nor sorrow will trespass on your peace. A little bit of work now, and great rest -- better said, everlasting joy -- is what you'll find. If you remain faithful and fervent in what you do, no doubt God will be faithful and generous in rewarding. Holding fast to a good hope is your duty: hope that you will attain victory, though without falling into complacency which leads to indifference or arrogance. 

There was a certain man who was anxious, going back and forth between hope and fear. At one point he was overwhelmed with grief and cast himself down in prayer before the altar in a church, and meditated within himself, saying, “Oh! if I only knew if I should persevere to the end.” He heard within him a voice from God, “And if you did know it, what would you do? Do now what you would do then, and you shall be very secure.” And quickly he was comforted and strengthened. He committed himself to God's will, and all that anxiety stopped. He didn't need to obsess curiously about his own fate and what would come of him, but turned his mind instead to what was the good and perfect will of God for the start and completion of every good work.

Hope in the Lord and do good, says the Prophet; dwell in the land and you will feed on its riches. The one thing that holds back so many from progress, from amending their lives, is the dread of difficulty. The ones who excel in virtue are the ones who are willing to do the hard work, to conquer those things within themselves which are most grievous and contrary to them. That's where a man makes the most progress and deserves greater grace, where he most overcomes himself and conquers his own spirit.

Imitation of Christ by Thomas A Kempis, 1.25 (first part).

Translation focused on contemporary English and preservation of rhetorical force and art