The following comes from Fr. George Rutler at Sunlit Uplands:
Before our present time, not so many people lived long enough for hips and knees to wear out. Memories also fade, but that problem of being old is not new: “Even if [your father’s] mind fails, be considerate of him; do not revile him because you are in your prime” (Sirach 3:13). A whole science is developing to stave off forms of dementia. There is also a spiritual dementia that forgets God, but the mystery of the Holy Trinity is the cure for forgetfulness. Pope Francis recently preached: “The Holy Spirit is God active in us, God who helps us remember, who awakens our memory. Jesus himself explains this to the Apostles before Pentecost: ‘the Spirit that God will send in my name will remind you of everything I have said.’”
The Risen Lord helped the two men on the Emmaus Road to remember the prophecies of the Resurrection. The Pope used the image of a road for Christian life: “Memory is a great grace, and when a Christian has no memory — this is a hard thing, but it's true — he is not a Christian; he is an idolater, because he is before a God that has no road, that does not know how to move forward on the road. Our God is moving forward on the road with us, He is among us, He walks with us. He saves us. He makes history with us. Be mindful of all that, and life becomes more fruitful, with the grace of memory.”
Through the Holy Spirit, the Blessed Mother had the Church’s best memory, and she “treasured up all these things, pondering them in her heart” (Luke 2:19). Spiritual memory is not like the reminiscence in which our culture engages on Memorial Day, for instance. That is an edifying piety, and Cicero said that to forget one’s past is to remain always a child. But the Holy Trinity transports the soul into an existence not limited by time. That is why the “memorial of the Eucharist” is an actual encounter with Christ and not a form of nostalgia.
We cannot know the full mystery of the Holy Trinity, but unlike oriental forms of mysticism which would obliterate consciousness altogether, we are given an eternal memory when we love the Father, Son, and Holy Spirit. The Beloved Disciple said, “We love Him because He loved us” (1 John 4:19). St. John lived until the third year of the reign of the emperor Trajan, which was 100 A.D. He may have had some gerontological decay, for he had to be carried about and kept repeating, “Little children, love one another.” When the Ephesian believers tried to “be considerate of him” by asking why he said only that, over and over again, he replied, “Because this is our Lord's command and if you fulfill this, nothing else is needed.”