Yes indeed it does oppose what Christ teaches. He is the only mediater and clearly stated so...catholics use many others than Him....They confess to a man Priest...when we are to confess to Christ...they pray to departed people...we are to make petitions to Christ alone...they see Mary as co-equal to Christ...He said He is the way, and the truth and no one can come to the father but by Him. So yes indeed they oppose Christ's teachings.
How Christ accomplishes the mediation is His choice.
“Jesus then breathed on the apostles.” The only other time God did this was to give life to Adam. Breathing on the Apostles was an extraordinary occurance and only happened twice in history.
John 20 :22-23 “ And when he had said this, he breathed on them [the apostles], and said to them, “Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained.”
“”Blessed are you, Simon, son of Jonah. For flesh and blood has not revealed this to you, but my heavenly father. And so I say to you, you are Peter, and upon this rock I will build my church and the gates of the netherworld shall not prevail against it. I will give you the keys to the kingdom of heaven; and whatever you bind on earth shall be bound in heaven; and whatever you loose on earth shall be loosed in heaven.” —Matthew 16:17-19
The Apostalic succession is very real and there is definitely a hierarchy that is established in this passage.