The same statement was repeated twice in the book of the Prophet Joel:
“Sanctify ye a fast, call a solemn assembly.”
(Joel 1:14, 2:15).
Call a solemn assembly, namely retire, so that you may find time for spiritual work.
In seclusion, you keep silent, and since you have no one to talk to, you talk to God. However, do not get secluded with sin or with wild thoughts, but do in order that your fast may not become visible to anyone except to your Father in Heaven who sees in secret. Moreover, it is know that one who fasts may be in such a state of asceticism, hunger, and weakness that one is unable to make any effort. Seclusion is thus more suitable for one.
In one’s fast, one’s soul is occupied with internal work with God. Speaking hinders one’s prayer, reverie, and contemplation. Meetings and visits hinder one’s devotion to God and may lead one into making mistakes.
In fasting, the Lord Jesus Christ retired to the mountain, in seclusion with God, the Father, and devoted Himself to contemplation…
Our Fathers’ fasts were performed in the same way in the wilderness… As for you, retire as best as you can, and if you are forced to mingle, do it within the limits of necessity. Rid yourself of lost time and of every extra word.
This brings to mind another fast which is:
Fasting of the tongue, thought, and heart:
Saint Isaac said: “the tongue’s fast is better than the mouth’s, and a heart’s abstinence from lust is better than the fast of both,” meaning that it is better than the fast of both the tongue and the mouth.
Many are those who concern themselves with the mouth abstaining from food. God rebuked them,
saying: “Not that which goeth into the mouth defileth a man; but that which cometh out of the mouth, this defileth a man.” (Matthew 15:11). In this way He shows us that wrong words are defiling. In the same way, our teacher the Apostle James refers to the tongue which “Defileth the whole body.” (James3:6). Is your tongue, thus, fasting with the fast of your body? And is your heart abstaining from lusts?
A fasting heart is capable or making the tongue fast with it, for “out of the abundance of the heart the mouth speaketh.” (Matthew 12:34). The Lord also said, “But those things which proceed out of the mouth come forth from the heart.” (Matthew 15:18). Moreover: “A good man out of the good treasure of the heart bringeth forth good things; and an evil man, out of the evil treasure, bringeth forth evil things.” (Matthew 12:35). Therefore, if your heart abstains from sin, your tongue will abstain from every evil word.
He, whose heart fasts, is also capable of having his body fast.
Therefore, what is important is for the heart and thought to abstain from every wrong desire. As for the fasting of the body, it is the least of all. Therefore, in your fast, control your tongue, and in the same way that you make your mouth refrain from food, make it refrain from bad talk. Control your thoughts and yourself.