A pastor (abbreviated to "Pr" or "Ptr" (both singular), or "Ps" (plural)) is the leader of a Christian congregation who also gives advice and counsel to people from the community or congregation. In Lutheranism, Catholicism, Eastern Orthodoxy, Oriental Orthodoxy and Anglicanism, pastors are always ordained. In Methodism, pastors may be either licensed or ordained.

Pastors are to act like shepherds by caring for the flock, and this care includes teaching. The New Testament typically uses the words "bishops" (Acts 20:28) and "presbyter" (1 Peter 5:1) to indicate the ordained leadership in early Christianity. Likewise, Peter instructs these particular servants to "act like shepherds" as they "oversee" the flock of God (1 Peter 5:2). The words "bishop" and "presbyter" were sometimes used in an interchangeable way, such as in Titus 1:5-6. However, there is ongoing dispute between branches of Christianity over whether there are two ordained classes (presbyters and deacons) or three (bishops, priests, and deacons). The first view is affirmed by the Presbyterian Church. On the other hand, Christians of the Roman Catholic, Persian, Eastern Orthodox, Oriental Orthodox, Moravian, Scandinavian Lutheran, Anglican, and Old Catholic, traditions maintain the latter view and affirm the doctrine of apostolic succession.

These terms describe a leader (e.g., bishop), one who maintains a careful watch for the spiritual needs of all the members of the flock (i.e., a pastor). The person must meet scriptural qualifications (1 Timothy 3:1-7; Titus 1:5-9). For some Protestants, whether called an elder, bishop, or pastor, these terms describe the same service in the church. In the early Church, only a man could be a presbyter, but many Protestant denominations in the 19th and 20th century have changed to allow women to be pastors. Whether man or woman, this person is to be older and experienced in the faith (i.e., an elder), a person who is a decision-maker, and a manager of church affairs.

The actual word pastor is derived from a Latin word meaning shepherd.