The devil knows this very well and tries in every way to spoil the joy he perceives we have or he instills evil and wrong thoughts in us, in order to take away our ability to rejoice…
Joy, my brethren, is, as I said, an important element in spiritual life… Joy quenches the thirst, relieves, gives spiritual strength and well-being to the soul and prevents the thoughts that may hinder us in our path towards God…
Learn to rise above any “misfortunes”, unpleasantness, failures, problems, etc., so that you can keep the joy of your spiritual life undiminished and unabated!
Make sure that you always have a joyful and pleasant disposition!… both towards God, and towards your fellow human beings, but also towards yourself!
If you face any adversity, do not compromise this joyful and grateful disposition!
Learn to rejoice in everything and always: Good, “bad,” pleasant and unpleasant… (But hate sin!)
Again, Saint Anthony tells us that “in no other way do we defeat the enemy than when, while we are being fought by him, we always rejoice spiritually!”
The necessity of joy is also confirmed by Godspoken Paul, when he categorically exhorts us (without leaving any room or exceptions):
“Rejoice always, pray without ceasing, give thanks in everything; for this is the will of God in Christ for you” (1 Thess. 5:16-18).
So, always and in all circumstances of your life, rejoice!
Constantly and unceasingly pray to God.
And for everything, whether pleasant or unpleasant, give thanks to God.
For this is the will of God that you should do, according to your relationship with our Lord Jesus Christ.