The first man to travel into outer space and orbit the earth was the Russian cosmonaut, Yuri Gagarin. Besides being a monumental human accomplishment, it was a source of pride for the Russian people to beat the West in sending a manned craft into space. And for the Soviet government, it was an opportunity to promote their atheistic, totalitarian regime. The Soviet premier at the time, Nikita Khrushchev, took the opportunity of his country's achievement to criticize religion by stating, "Yuri Gagarin flew into space and didn't see God there."
Of course, as is so often the case with atheists, Khrushchev's comments show a basic ignorance about God. God does not live in outer space. God is not out in the universe floating around somewhere. Rather, he is outside the universe. No spacecraft could ever travel far enough or fast enough to reach him. God is outside space and time. There is no way for us to get to where God is. God is greater than this vast universe for he created it.
In fact, if God had not revealed himself first to the Jewish people through the covenant with Abraham and later to the whole world through Jesus Christ, there is no way we could come to a full knowledge of him. Through the wonders of nature we would have some glimpse into his power and wisdom. Through our human ability to love and care for each other, we would have some sense that he is good. But if he had not sent Jesus Christ, we would not know that he is a personal God who knows each of us by name and who wants us to have a relationship with him. And we could never have imagined how limitless his love for us is that he would send his only Son to die for us. It is only through Jesus that we can know God in all his mystery and only by the gift of the Holy Spirit that we can love him in return.
Nothing illustrates this more than the mystery we celebrate today, the mystery of the Holy Trinity. We love and worship one God who is three persons, Father, Son and Holy Spirit. Though three persons, they are one God. Though one God, they are three persons. We call it a "mystery" because our human intelligence can never fully understand it. If God had not revealed this truth to us through Jesus and through the Church, we could never have known it. As it is, only when we are in heaven, outside the bounds of space and time, will we glimpse fully the reality of God's mystery.
Because God dwells in mystery outside of the universe, there is no way that our human efforts alone can reach him. Just as there is no spacecraft that can travel to where he dwells, there are no amount of good deeds we could perform to earn our way into heaven. If it were possible to enter heaven simply be being good and not hurting each other, it would not have been necessary for Jesus to have suffered and died on the cross. Salvation is not a result of our efforts or good intentions. Rather it is a gift offered to us out of the love of God who created us to live eternally with him in heaven.
That is why Saint Paul tells us in today's second reading that we are justified by faith. As he uses the term, justification means that our friendship with God is restored. Sin destroyed our relationship with God, but Jesus restored it by dying on the cross for our sins. It is because of Jesus' effort, not our own, that our relationship with God is restored. For us to be saved, we need to believe not just that God exists, but that he sent his Son to die for us and that our sins are forgiven in his name. We need to have faith. And we have already received that faith through baptism.
You will notice that I said that our human efforts alone cannot get us to heaven. That is not to say that our efforts have no value or that we should not strive to be good. Rather our efforts assisted by God's grace are pleasing to our heavenly Father. When we add God's love to whatever we do, it has immeasurable worth. The gift of salvation is given to us freely, but we must accept it and put it to use in our lives. We have to strive to be good with the help of God, understanding all the while that even our ability to do good is a gift of God.
Science can never develop a spacecraft capable of reaching God. We could never engineer a computer program capable of unraveling the mystery of a God who is Father, Son and Spirit. No one could ever write a self-help book that could help us once and for all conquer sin. Since we could not travel to God, he traveled to us. In Jesus Christ, God revealed himself to be a Father who created us, a Son who saved us and a Spirit who makes us holy. We do not have to figure it all out or try to understand it. We need only accept the gift and rejoice that our God loves us so much. The mystery comes down to one simple fact - this God who dwells in mystery loves us, and he wants us to love him in return.