There are people in our schools that are extremely important. As a teacher, I value the contributions of substitute teachers, for without them many academic instittutions would be forced to close its doors. It is comforting to know that when I have to miss school for any reason, a substitute will take my place. Nowadays, substitutes are just a click away on my computer. Finding a good substitute is another story.
This world is also filled with substitutes. There is a bunny in the spring, a turkey in the fall and red clad fat man in the winter. They, along with many others are very poor (and evil) substitutes of our Lord Jesus Christ. Since the creation of the world, mankind has looked for many substitutes to worship them instead of the blessed Creator. We have worshipped all the hosts of heaven and the beasts of the field. Even Israel, the redeemed people of God, worshiped a golden calf or bull, instead of praising their Deliverer.
Christianity is no exception to the rule. The church of Jesus Christ started well and it expanded to all the known world, but soon heresies, idols and false teachers infiltrated our ranks. The Roman Catholic church is a clear example of this perversion. Their local "churches" look like old pagan temples filled with idols (they call them saints and virgins), candles, incense and chants. The worst and most blatant substitution of all is the Pope. He is the bishop of Rome, the Pontifex Maximus and the vicar of Christ on earth. This last title (vicar) means that he is Christ's substitute in this world.
There is no substitute for Christ! No one can take his place; not the pope, not church leaders, not famous preachers or Christian singers. There is only one Jesus, the only begotten Son of God and God in the flesh. He will never share his divine glory with anyone. Teachers and pastors need substitutes from time to time, but Jesus is irreplaceable, indivisible, and indispensable.
The most beautiful part of all this is that Jesus is our eternal Substitute. He died on the cross in our place and He intercedes on our behalf every day before the Father. Furthermore His substitutionary work reaches every part of our lives, in fact, our lives are not our own for He bought us with His blood (1 Corinthians 6:20) and has substituted His life for ours (Galatians 2:20).