Fasting Before Holy Communion
“In older days, many Christians were receiving Holy Communion, especially before Pascha, without preparation. The Fathers, seeing the harm that was being caused by this, established the 40 days of fasting and prayer as a preparation.” -St. John Chrysostom (Against the Judaeans 3. P.G.47:867)
Christians were being harmed by not preparing for Holy Communion through fasting and prayer.
The greatest feasts of our Church are preceded by a fast.
The Apostolic Canon says that Saturdays are not fasted. Fasting in this sense means: Not eating anything at all, keeping the ninth hour, and then eating only one food, etc., etc.
The Apostolic Canon does NOT say that every Saturday has a dispensation to eat of all foods. This is clarified in the writings of the 6th Ecumenical Council.
Our confessor/spiritual father should advise us as how to prepare for this great mystery.