The office of the pastor is threefold. The Scriptures teach that the man has three functions in his office. He is usually called by the title “Pastor” because of the relational aspect of that part of the ministry. He could also be justly called by the titles “Elder” or “Bishop”. What the world has done in the designation of these terms is irrelevant. The titles must be seen and used in the manner in which they are given in God’s Word.
The word “elder” is used of both a man that is “old” in age and then also of a man that displays the characteristic of wisdom. The Scriptures state that “elders’ were ordained, or set apart, “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 AV), into the work of leading the churches in their cities., “Let the elders that rule well be counted worthy of double honour, especially they who labour in the word and doctrine”. (1 Timothy 5:17 AV)
The word “bishop” shows the business side of the pastor. He is to be an able overseer of the work. “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 20:28 AV)

The pastor is the shepherd of the sheep, the minister of God, And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers; (Ephesians 4:11 AV). He tends to them and makes sure that they are healthy and productive. The Lord was very straightforward with Peter in this position. The shepherd of the sheep must realize Whose they are and that he is being held responsible to care for them. The pastor is the shepherd of the flock, but he does not own the flock. There is a greater Shepherd that owns the flock and requires and accounting. The pastor is to shepherd the church in love, his love for Jesus constrains him to serve well for the glory of the Lord. “Obey them that have the rule over you, and submit yourselves: for they watch for your souls, as they that must give account, that they may do it with joy, and not with grief: for that is unprofitable for you. Pray for us: for we trust we have a good conscience, in all things willing to live honestly. But I beseech you the rather to do this, that I may be restored to you the sooner. Now the God of peace, that brought again from the dead our Lord Jesus, that great shepherd of the sheep, through the blood of the everlasting covenant, Make you perfect in every good work to do his will, working in you that which is wellpleasing in his sight, through Jesus Christ; to whom be glory for ever and ever. Amen. And I beseech you, brethren, suffer the word of exhortation: for I have written a letter unto you in few words. Know ye that our brother Timothy is set at liberty; with whom, if he come shortly, I will see you. Salute all them that have the rule over you, and all the saints. They of Italy salute you.” (Hebrews 13:17-24 AV)

The book of Acts uses the terms according to the normal and proper Biblical meaning and so defines them precisely. As the Apostle Paul was preparing for his visit to the city of Ephesus on his way to Jerusalem, he sent a message to the elders so that they would be prepared for his coming. “And from Miletus he sent to Ephesus, and called the elders of the church.” (Acts 20:17 AV) As he was speaking to these elders, it is noted that he gave them instructions according to the functions of their office. “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 20:28 AV) It should be duly noted that they did not take upon themselves this ministry, neither did the church hire them to fill a position, but that God called them and placed them according to His will. Again note that these men were elders. These elders were instructed in the work before them as pastors – they had a flock and they had to feed them. They were shepherds/pastors over the flock/church of God. These elder/pastors had also been given the responsibility to oversee/bishop the church which belongs to God. Paul instructed the elder/pastor/bishop in the ministry that was given to them. Every pastor has this ministry and as a steward, is accountable to carry out these ministries to the glory of God.