[We] must affirm Christ's objective presence in the Eucharist, and must maintain that “Spiritual Communion” is not the same as the Eucharist. We can understand liturgical contemplation and “Spiritual Communion” as receiving the grace of the Holy Spirit by recalling the sacraments we have already received, recalling our baptism, which is praised by the Early Fathers as a fountain of repentance and reconciliation with God. St. Isaac the Syrian says that tears of repentance over sin is a “renewal of baptism” or a “return to baptismal waters,” and praises those who contemplate the mysteries in a spirit of reverence and prayer. Spiritual communion can be remembering our Communion with Christ and asking God for the outpouring of His grace through that physical, temporal and actual connection with Him. It is a return to the objective realities of Christ’s presence in the Sacraments and a meditation upon that truth. “Our insistence on the reality of the Eucharist has to be stressed, and as such, spiritual communion has to be understood as a pastoral devotion in times of plague or persecution when the faithful cannot access a priest or parish to receive the Eucharist. We have to be on guard against is the idea that Spiritual Communion is normative or even gives the exact same grace as receiving the Eucharist.” (Quote from Christopher Barber)
Properly understood, Spiritual Communion is a devotion that looks backward and forward, like many of the sacraments themselves, connecting us with that which has been received and what will be manifest of God's grace, according to His Will. It is not the same act, or "essentially the same", as the act of communion. it is a meditation on Communion, a prayer for God’s Grace, and a anticipation of the time when we can be united once again with our Brothers and Sisters in the Eucharistic Reality of our Local Church the the Sacrament of Christ’s Body and Blood. It is, as Cabasilas and St. Germanus insisted, a mystical contemplation on the meaning of Communion, and a prayer that may, by God’s mercy, avail us to sustaining grace for the difficult days ahead by the Mercy of Christ and the Power of the Holy Spirit.