In the West it was considered important that those receiving Communion understand exactly Whom they are receiving. By delaying First Communion until the age of reason, children may be taught before the reception of Communion that they are being privileged to receive the body, blood, soul, and divinity of Jesus Christ. By making First Communion an informed choice of the person receiving it, that person might better appreciate the gift he is receiving.
This is not to say that the Eastern practice cannot be equally well defended as a helpful spiritual practice. It could be argued that in the East children are nourished from their very cradles by Christ himself and, since they are incapable of personal sin until the age of reason, there is no need to deny them this great gift. Different churches within the universal Church have different approaches to the sacraments, and there is room within the universal Church for a legitimate pluralism in sacramental theology and pastoral care.
