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Be alert and diligent in the service of God, thinking often why you were born and why you have left the world. Was it not that you should live only for God and become a spiritual person? Certainly it was.
Therefore, set your heart on striving for perfection, for shortly you will be rewarded for all your labors and after that you will never experience sorrow and dread.
Your labor will last but a short time and then you will receive everlasting rest and peace. If you are faithful and fervent in doing good, there is no doubt that God will be faithful and generous in His reward.
Have a firm hope that you will attain the victory; but do not presume this, for then there is danger of your becoming careless and proud.
Therefore, set your heart on striving for perfection, for shortly you will be rewarded for all your labors and after that you will never experience sorrow and dread.
Your labor will last but a short time and then you will receive everlasting rest and peace. If you are faithful and fervent in doing good, there is no doubt that God will be faithful and generous in His reward.
Have a firm hope that you will attain the victory; but do not presume this, for then there is danger of your becoming careless and proud.
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Thomas a Kempis Imitation of Christ: Book 1, Chapter 25, Number 1 (via catholic-inspiration)