Communion - How Many Times Daily
One of the significant changes for the faithful in the Code of Canon Law which was promulgated in 1983 was the permission to receive Holy Communion more than once per day. In the past the law set certain conditions, such as participation in a funeral, marriage or ordination Mass. The new canon, however, simply states,
c.917 A person who has received the Most Holy Eucharist may receive it again (iterum) on the same day only during the celebration of the Eucharist in which the person participates, with due regard for the prescription of can. 921, part 2.
What it is saying is that if one attends a Mass after receiving Holy Communion previously that day, one may receive it again. If it is not a Mass, but a Communion Service for example, one may not receive again.
However, since the Church encourages the full participation of the laity in the Masses they attend, including Holy Communion (if they are worthy), the question arose whether this canon might not permit Holy Communion in any Mass, regardless of the number of times one attended per day. After numerous bishops asked this question of the Holy See, the Pontifical Commission for the Authentic Interpretation of Legislative texts gave the following authentic interpretation, approved by Pope John Paul II,
Doubt: Whether, according to canon 917, one who has already received the Most Holy Eucharist may receive it again on the same day only a second time, or as often as one participates in the celebration of the Eucharist.
Response: Affirmative to the first; negative to the second. [AAS 76, (1984) 746]
In the accompanying commentary it was explained that the meaning of again (iterum) was to allow a second time, but not a third, fourth etc... The exception to this is the one given in the law itself, canon 921, 2.
2. Even if they have received Communion in the same day, those who are in danger of death are strongly urged to receive again.
Thus, Communion given as Viaticum may be received at any time.
One final note, this law applies to Latin Rite Catholics. Iin the Eastern Catholic Churches the practice of frequent daily Divine Liturgy (Mass) is not found, and so the Code of Canons of the Eastern Churches is silent on this matter.