Hieromonk Gregorios: On how to rightly receive the Holy Eucharist

 Every Christian should imitate Joseph, who "took the Body of Jesus, wrapped it in a clean winding sheet and placed it in a new tomb" (cf. Matt 27:59-60) - which is to say, in a new person. Let each one of us therefore take diligent care not to sin, so as not to show contempt for God who dwells within us and expel Him from our soul. The soul of every Christian believer becomes a "new tomb" which will receive the all-holy Body of Christ.

+Hieromonk Gregorios, from The Divine Liturgy a commentary in the light of the Fathers, chapter 3 The Litany and the Great Entrance.

St. John Chrysostom: On how to approach the Holy Gifts

 Having taken account of the magnitude of the Sacrifice, make your body beautiful. Understand what your hand receives, and never raise that hand to strike someone... Bear in mind that you do not receive Christ in your hand only but also put Him into your mouth, and keep your tongue pure of foul and abusive language, free from blasphemies and perjury... When you recall that your heart receives that terrible Mystery, never scheme against your neighbor but keep your heart pure of any wickedness. In this way you will also be able to guard your eyes and your hearing... You are invited to a wedding my beloved; do not go in wearing dirty clothes, but provide yourself with the appropriate garment (cf Matt 22:2-14).

+St. John Chrysostom, from Baptismal Instructions, 2.2.