December 20 
O Key of David, opening the gates of God’s eternal kingdom, come and free the prisoners of darkness!
What is the significance of a key and particularly a key that opens the gates of God’s kingdom?
Keys are used to unlock things. We are told in this prayer that a key is NEEDED to unlock God’s kingdom. This tells us that (1) God’s kingdom was shut before Jesus Christ – humanity was not able to enter, (2) Christ is the key that gives all humanity access to God’s kingdom, and (3) those who enter God’s kingdom are freed from darkness (sin).
I have written about the reality of sin and our need for grace here. But as a short summary, in the beginning, God created Adam and Eve, the first man and first woman. He gave them all that they needed and they were in communion with God. But God needed to test their love – would they freely choose to love God or would love choose themselves over God? Adam and Eve rejected God and His love by disobeying God thus sinning and turning away. As a result they were expelled from the Garden of Eden and this first couple and the rest of humanity no longer had access to God and His grace. Heaven – God’s eternal kingdom – was closed off to humanity.
But God’s love is unconditional and He offered humanity another chance. In the fullness of time God sent His only Son Jesus to become man. Then Jesus out of love offered Himself freely as a sacrifice for us, suffering torture, humiliation, abandonment, crucifixion and death. This death on the cross was an act of redemption. Jesus died for the sins for the whole world. His sacrifice was a pure offering to God because He was perfect and sinless. He offered His human life but at the same time His offering was of infinite value because Jesus was also God.
In this act, Jesus opened the gates of heaven – humanity now once again had access to heaven. After Jesus rises from the dead, He then ascends into heaven definitively opening the gates of heaven forever. Now heaven is possible for all men.
In this same act on the cross, Jesus also offers grace to each and every human person. This grace is the divine life that can abide within us. This divine life is a supernatural power that enables us to love, have faith, be obedient to God and ultimately to enter heaven. If we allow grace – this divine life – to abide within us, it gives us the power to resist temptation and sin. We can then walk in the light rather than in the darkness. With grace, sin no longer reigns in our hearts but rather we have the life of the Spirit within us. Each day we must choose to cooperate with grace as throughout this earthly life we are on a journey. We must persevere on this path of grace until the end and then we will be able to enter heaven and be with God in His eternal kingdom.
