Pastors are leaders of local, autonomous congregations. These men are selected from among the congregation they serve, and they must meet stringent qualifications listed in 1 Timothy 3 and Titus 1.
In the denominational world, the term pastor almost always is used with reference to the preacher. Almost always, again, this preacher is singularly in charge of the people to whom he preaches. These are just a couple more of man’s many, many departures from the biblical pattern. Pastors, bishops, elders, and shepherds are all equal terms that refer to this same office. In churches of Christ, the term elders is clearly preferred, but we should note that all of the above-listed terms are scriptural, and each focuses on a certain dimension of the work.
Preachers (who do not hold the office of a bishop) are not pastors. Naturally, a man may be both an elder and a preacher. In such a case, this man would be a pastor because he belongs to that office (but not because he’s a preacher).
This matter is one of the many differences between the Lord’s church and denominations. It may seem like a small matter to some, and to be sure, there are more drastic differences observable between the Lord’s church and denominations. This, though, is an area of denominational creep (kind of like the religious world’s version of carb creep) that some decide to let be. In the spirit of being faithful in little so we can be trusted in much (Luke 16:10), let’s keep our terminology tight and distinct. Members of the church of Christ come (in part) from a proud call to get back to the Bible and speak where the Bible speaks. -Dustin