If Prime Minister Stephen Harper did pocket the Eucharist after receiving it, was he correct in doing so? Absolutely not.
What is the Eucharist?
The Holy Eucharist is the most important of the seven sacraments because, in this and in no other sacrament, we receive the very body and blood, soul and divinity of Jesus Christ. Innumerable, precious graces come to us through the reception of Holy Communion.
If one reads the accounts of the Last Supper in the Gospels, Jesus took bread and wine and declared it His Body and Blood. It is from this that Catholics celebrate the Eucharist. It is through transubstantiation that flour wafers and wine are made in Christ's Body and Blood. After this "process", one must consume the Body of Christ, not misplace it.
Who can receive Communion and under what conditions?
The Church sets out specific guidelines regarding how we should prepare ourselves to receive the Lord’s body and blood in Communion. To receive Communion worthily, you must be in a state of grace, have made a good confession since your last mortal sin, believe in transubstantiation, observe the Eucharistic fast, and, finally, not be under an ecclesiastical censure such as excommunication.
"Because Catholics believe that the celebration of the Eucharist is a sign of the reality of the oneness of faith, life, and worship, members of those churches with whom we are not yet fully united are ordinarily not admitted to Communion. Eucharistic sharing in exceptional circumstances by other Christians requires permission according to the directives of the diocesan bishop and the provisions of canon law. . . . "
Another reason that many non-Catholics may not ordinarily receive Communion is for their own protection, since many reject the doctrine of the Real Presence of Christ in the Eucharist. Scripture warns that it is very dangerous for one not believing in the Real Presence to receive Communion: "For any one who eats and drinks without discerning the body eats and drinks judgment upon himself. That is why many of you are weak and ill, and some have died" (1 Cor. 11:29–30).
These are the conditions, which Harper does not meet. He is not a Catholic, no doubt does not believe in transubstantiation, is not in a state of grace, nor (as it would seem) does he now how to partake in this sacrament.
Neither did the prime ministers before him.