252 Q. How are we united to Jesus Christ in the Holy Eucharist?  A. We are united to Jesus Christ in the Holy Eucharist by means of Holy Communion.

253 Q. What is Holy Communion?  A. Holy Communion is the receiving of the body and blood of Christ.

Holy Communion is therefore the receiving of the Sacrament of Holy Eucharist.

254 Q. What is necessary to make a good Communion?  A. To make a good Communion it is necessary to be in a state of sanctifying grace, to be fasting for one hour, and to have a right intention.

“Fasting”—­that is, not having taken any food or drink for one hour before the time of Communion. (Water and true medicine do not break the fast and may be taken at any time.) What, then, are you to do, if, without thinking, you break your fast?  Do not go to Communion at that Mass; you can remain in church and receive Communion at the following Mass.  Never, never, on any account, go to Holy Communion when you have broken your fast.  Never let fear or shame or anything else make you do such a thing.  It is no shame to break your fast by mistake; but it is a great sin to knowingly go to Communion after breaking your fast.

“A right intention”—­holy and spiritual motive, such as, to obey Our Lord’s command, to receive strength to resist temptation, or to be united with Our Lord.

255 Q. Does he who receives Communion in mortal sin receive the body and blood of Christ?  A. He who receives Communion in mortal sin receives the body and blood of Christ, but does not receive His grace, and he commits a great sacrilege.

“The body and blood,” because the appearance of bread and wine is there after consecration, and he receives it.  He who receives the Holy Eucharist in mortal sin receives Our Lord into a filthy soul.  If a great and highly-esteemed friend was coming to visit your house, would you not take care to have everything clean and neat, and pleasing to him?  And the greater the dignity of the person coming, the more careful you would be.  But what are all the persons of dignity in the world—­kings or popes—­compared with Our Lord, who leaves the beauties of Heaven to come to visit our soul? and the purest we can make it is not pure enough for Him.  But He is kind to us, and is satisfied with our poor preparation if He sees we are doing our very best.  But oh, what a shame to receive Him into our soul without any preparation! and more horrible still, to fill it with vile sins, that we know are most disgusting to Him!  No wonder, therefore, that receiving Holy Communion unworthily is so great a crime, and so deserving of God’s punishment.  Why should not the heavenly Father punish us for treating His beloved Son with such shameful disrespect and contempt?

256 Q. Is it enough to be free from mortal sin, to receive plentifully the graces of Holy Communion?  A. To receive plentifully the graces of Holy Communion it is not enough to be free from mortal sin, but we should be free from all affection to venial sin, and should make acts of lively faith, of firm hope and ardent love.