The phrase "Communion of Saints", which we profess in the Creed, is our participation in the life of the Holy Trinity with all those who believe in Christ. Our Lord Jesus Christ holds all who believe in Him, in His love. We are one with Christ and, therefore, one with our brothers and sisters in Christ in this world, in Purgatory, and in Heaven. 

At Mass the "Communion of Saints" is realized and fulfilled in this world. At every Mass the Kingdom of God is revealed. In the words of the Roman Canon we pray, "Bid your angel to take this sacrifice to your altar on high, that we, receiving from this altar may receive the body and blood of your Son..." Space and time are overcome and we are present before the "Lamb that was once slain and lives forever". 

Next to Holy Communion with our Lord at Mass we are in communion with His Mother and ours, the Blessed Virgin Mary. At Calvary's cross our Lord gave us to Mary to be Her children and gave Mary to us to be our Mother. At Calvary's cross our Blessed Mother offered Her pain and suffering with His for our salvation. The sword that pierced His Sacred Heart pierced Her Immaculate Heart as well. In Her Assumption, Body and Soul into heaven, Our Lady continues to stand next to the "Lamb that was slain and lives forever" to offer Her suffering and sorrows with Her Son for us. As she shared Christ's pain and suffering, she shares ours, if we give them to Him through Her. 

At every Mass our Mother and Queen is present united to Her Son and united to us, Her children. The intimacy of our union with Him through Her is understood when we contemplate that His Body and Blood come from Her and Her spouse, the Holy Spirit.  When next at Mass pray to the Holy Spirit to open your eyes of faith to the Kingdom of God revealed in our communion with the Saints.

Then we can begin to understand our Blessed Mother's title: Our Lady of the Most Blessed Sacrament.