One way that human institutions insure unity is by means of a hierarchy or chain of command devolving from one individual at the top. Since individuals are relatively self-consistent, this assures some degree of unity of law and policy, at least during the lifetime or term of the leader.
That is not Christ's way. The Bible clearly teaches that it is God the Holy Spirit who maintains the unity of the church (Eph. 4:4-5, I Cor. 12:13). Individual members are only commanded to love one another, and the Lord will insure unity among the believers.
A hierarchy implies that people are separated into ranks or levels of importance within the body. That is contrary to the Bible's emphasis on the equality of believers, the priesthood and sainthood of all believers (Gal. 3:28, 2 Cor. 8:13, I Pet. 2:9, Phil. 1:1). There are no grounds for favoritism; we should all hold each other in high regard (Rom. 2:11, James 2:1). All are servants of one another (Eph. 5:21). "If one part suffers, every part suffers with it; if one part is honored, every part rejoices with it." (I Cor. 12:26 NIV).