The Fourth and Final Mark: Apostolic

The Church is apostolic. Christ founded the Church and entrusted His authority to the Apostles, who were the first bishops. He entrusted a special authority to Saint Peter, the first Pope and Bishop of Rome, to be his Vicar here on earth. This authority has been handed down through the Sacrament of Holy Orders in apostolic succession. The bishops that are alive right now can trace their authority all the way back to one of the original twelve Apostles that were alive during the time of Christ. Apostolic succession is from bishop to bishop and these bishops ordain priests and deacons to assist them with their work. Bishops are in charge of areas called diocese and these bishops ordain priests to run a specific church inside of the diocese. This is all part of something called the Hierarchy of the Church. That was just a little bit of background information about the bishops because they play such a big role in the Church being apostolic.
We can also see the mark of apostolic through the Deposit of Faith. The Deposit of Faith is found in both Sacred Scripture and Sacred Tradition and it was preserved, taught, and handed on by the Apostles. Under the guidance of the Holy Spirit, the Magisterium has the duty to preserve, teach , defend, and hand on the Deposit of Faith.