Saint Basil the Great (Church Father)

“What is the mark of a Christian?  That he be purified of all defilement of the flesh and of the spirit in the Blood of Christ, perfecting sanctification in the fear of God and the love of Christ, and that he have no blemish nor spot nor any such thing; that he be holy and blameless and so eat the Body of Christ and drink His Blood; for ‘he that eateth and drinketh unworthily, eateth and drinketh judgement to himself.’  What is the mark of those who eat the Bread and drink the Cup of Christ?  That they keep in perpetual remembrance Him who died for us and rose again.” (The Morals, [Ch. 22])
 
To communicate each day and to partake of the holy Body and Blood of Christ is good and beneficial; for He says quite plainly: ‘He that eats My Flesh and drinks My Blood has eternal life.’  Who can doubt that to share continually in life is the same thing as having life abundantly?  We ourselves communicate four times each week, on Sunday, Wednesday, Friday, and Saturday; and on other days if there is a commemoration of any saint.” (Letter to a Patrician Lady of Caesaria, [93], (c. 372)
 
(Cf. Michael Cuozzo, Theological Aspects of Worshipping God in the Holy Eucharist (Unpublished doctoral dissertation). Northwestern Theological Seminary, Florida, 2006), p. 19)