Autonomous: Not under the control of another. Baptist churches are not under the control of a denominational body. Each church owns its own property, calls its own ministers, and runs its own affairs as it sees fit, hopefully under the leadership of Christ.
Baptism of the Spirit: When the Holy Spirit comes to indwell the believer and to make him or her a part of the body of Christ, the Church. Some Christians believe the Baptism of the Spirit happens as a second experience after a person has become a Christian. They see it as a special experience with the Holy Spirit. the Bible teaches that this baptism takes place at the same time we are made part of the body of Christ, that is saved.
Believers Church: Baptists, among others, teach that a church should be made up only of believers and only of those who have freely chosen to be members. One is not “born into” a believers church.
For more definitions, click here.