a) What is Holy Communion?
Holy Communion is receiving Jesus Christ in the sacrament of the Holy .
Eucharist. To receive the Holy Eucharist worthily, it is necessary: to be free from mortal sin; to have the right intention; and to abstain from eating and drinking, except water and medicine, one hour before (except for the sick and elderly, and those caring for them).
The principal effects of a worthy Holy Communion are: it unites us more with Jesus Christ and the Church; it increases sanctifying grace; it defends us from mortal sin and takes away venial sin; and it lessens our inclination to sin and helps us to lead a holy life.
b) Why should an Altar Server receive Holy Communion worthily?
Only if Holy Communion is received worthily can we obtain its graces. One who knowingly receives it in the state of mortal sin physically receives the Body and Blood of Christ, but not his graces; instead, he further commits another mortal sin, that of sacrilege.
An Altar Server should encourage his friends through his example to show devotion to the Holy Eucharist by receiving our Lord devoutly and often, even daily if possible. He should also spend some time in prayer for preparation before Mass and for thanksgiving after Holy Communion.