In the Jewish practice, there are two types of fast– the major and minor fast- and they are ceremonial (to bring to remembrance). Each fast signifies something and such things are to be promoted on such days Isaiah 58:6 (in addition to abstinence from eating).
Believers’ fast is not ceremonial but a resolute separation unto God (demeaning the flesh and uplifting the spirit) which could be by an individual or a group. The flesh survives on what it perceives and feels (like food, pleasurable activities etc) but the spirit survives on rhema Matthew 4:4. The spirit has its voice which is accentuated when you fast.
Believers’ fast is not a new concept. During the time of Jonah, men of Nineveh separated themselves unto God, likewise Moses when he went to the mountain to get the 10 commandment and Jesus when he fasted for 40 days and 40 nights. Esther, Daniel, and David used it in their days because they understand that their cry to heaven is loudest when they mourn (fast).
When Jesus said disciple needed no fast, he was referring to Jewish fast not believers’ fast because he himself partook in it with his disciples regularly. You do not praise a chief when the king is on seat which is why Jesus said it was not proper for his disciple to fast when he is with them but when he is no more with them, they can fast.
Believers’ fast has been shown to be very potent as it ensures unlimited presence of God.
The wisdom is this- you do not have to wait for the spirit of God to draw you, you can initiate by calling yourself into separation unto God to feed your spirit.
It is a good thing that the church as a platform provides such opportunities for you, and you should maximize it for your upliftment.