The primary role in shepherding the New Testament churches was exercised, not by a solitary Pastor, but by a plurality of men, described as "elders" or overseers
And when they had ordained them
elders in every
church, and had prayed with fasting, they commended them to the Lord, on whom they believed. (Acts 14:23)
From Miletus he sent to Ephesus and called for the
elders [plural] of the
church[singular] ....
He said unto them...Take heed therefore unto
yourselves, and to all the
flock, over the which the Holy Ghost hath made you
overseers, to feed the
church of God, which he hath purchased with his own blood. (Acts 20:17-28)
Paul and Timotheus, the servants of Jesus Christ, to all the saints in Christ Jesus which are at Philippi, with the
bishops and deacons: (Phil. 1:1)
For this cause left I thee in Crete, that thou shouldest set in order the things that are wanting, and ordain
elders in every city, as I had appointed thee: (Titus 1:5)
Is any sick among you? let him call for the
elders of the church; and let them pray over him, anointing him with oil in the name of the Lord: (James 5:14)
The quotation above from Acts 20 makes it clear that the "elders" and "overseers" are the same persons, and that it is they who are given responsibility to shepherd, or pastor the church of God.
The elders which are among you I exhort, who am also an elder, and a witness of the sufferings of Christ, and also a partaker of the glory that shall be revealed: Feed the flock of God which is among you, taking the oversight thereof, not by constraint, but willingly; not for filthy lucre, but of a ready mind; (1 Peter 5:1-2)
Here is the
ONE time the word "pastor" is in the New Testament.
Ephesians 4:11
And he gave some, apostles; and some, prophets; and some, evangelists; and some,
pastors and teachers;
Again it is plural.
The terms "Bishop, Elder, Pastor, Overseer, and Shepherd" generally refer to the same office.
There is not one instance of a New Testament assembly being presided over by a single pastor. (other than 1 Pet 5:4

) Timothy and Titus were never refered to as "pastor". They were functioning in the role of apostle (church planters). When they accomplished their goal (Setting up elders to rule the church - see Titus 1:5 above), they moved on to other business just like Paul.
Note the following texts (where either elder or bishop is used):
Acts 11:30--elders at the church of Antioch
Acts 14:23--Paul and Barnabas appoint "elders in every church"
Acts 15:2, 4, 6, 22, 23; 16:4--elders at the church in Jerusalem
Acts 20:17, 28--elders/bishops at the church of Ephesus (v. 17--"elders of the church")
Acts 21:18--elders at the church in Jerusalem
Phil 1:1--the church at Philippi has bishops and deacons
1 Tim 5:17--elders at the church of Ephesus
Titus 1:5--Titus is to appoint elders in every town
Jas 5:14--"the elders of the church"
1 Pet 5:1-2--"the elders among you"8
In every one of these texts the plain implication is that each church had several elders.
lacy