Is it the pastor? Church leaders? Church members?

These people all play a vital role in the church and the life of the church’s ministry. Their leadership is needed and useful.

But the ultimate authority of the church is Jesus Christ, who is the cornerstone of the church.

“This Jesus is the stone that was rejected by you, the builders, which has become the cornerstone” (Acts 4:11, ESV)

“So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God, built on the foundation of the apostles and prophets, Christ Jesus himself being the cornerstone, in whom the whole structure, being joined together, grows into a holy temple in the Lord. In him you also are being built together into a dwelling place for God by the Spirit” (Ephesians 2:19-22, ESV).

In the New Testament, Jesus established the church. The apostles were given a place of leadership and authority.

“And he gave the apostles, the prophets, the evangelists, the shepherds and teachers, to equip the saints for the work of ministry, for building up the body of Christ” (Ephesians 4:11, 12, ESV).

Jesus is the foundation of the church. Any church not built on the Lord, and following His Word, is not Christ’s church. Furthermore, any church or building not established by the Lord is built in vain. The people’s labor is for nothing.
“Unless the LORD builds the house, those who build it labor in vain. Unless the LORD watches over the city, the watchman stays awake in vain.” Psalm 127:1, ESV).

However, God wants to teach us about loving leadership as well. That’s why He sends the Holy Spirit to us, who gives us spiritual gifts we can use for the building up of His Church.

The early church recognized the need for this leadership among their community to further the gospel commission. Prayerfully, they made the decision to delegate various ministry jobs to members of the church with such gifts (Acts 6:1-6).
The early church grew and so did its organization. But the authority of the church and church leaders always remained in Jesus Christ.
“Religion that is pure and undefiled before God, the Father, is this: to visit orphans and widows in their affliction, and to keep oneself unstained from the world” (James 1:27, ESV).

THE CHURCH IS THE BODY OF CHRIST.

The church as a community of believers is described as the body of Christ. This beautiful metaphor illustrates the diversity of Jesus’ worldwide community of followers. It also shows how each member of the church is important.

Each Christian has a role to play in God’s work. Everyone has been given unique talents and special gifts they can use in their own ministry.

If the church is the body of Christ, we see that Jesus is the head and each believer is a different member of the body.

“And he is the head of the body, the church…” (Colossians 1:18, ESV).

“For as the body is one and has many members, but all the members of that one body, being many, are one body, so also is Christ. … Now you are the body of Christ, and members individually” (1 Corinthians 12:12, 27, NKJV).

“From whom the whole body, joined and held together by every joint with which it is equipped, when each part is working properly, makes the body grow so that it builds itself up in love” (Ephesians 4:16, ESV). 

“For the body does not consist of one member but of many. If the foot should say, “Because I am not a hand, I do not belong to the body,” that would not make it any less a part of the body” (1 Corinthians 12:14, 15, ESV).

Just as the body needs each organ to survive, each part of the Body of Christ is essential as well. This is to illustrate that every person, no matter their gifts or talents, is valuable and has a purpose in the Church.

--An excerpt taken from: https://www.adventist.org/the-church/