And I will give you shepherds after my own heart, who will feed you with knowledge and understanding.
Jeremiah 3:15 (ESV)
The Book of Church Order:
8-1. This office is one of dignity and usefulness. The man who fills it has in Scripture different titles expressive of his various duties. As he has the oversight of the flock of Christ, he is termed bishop or pastor. As it is his duty to be grave and prudent, an example to the flock, and to govern well in the house and Kingdom of Christ, he is termed presbyter or elder. As he expounds the Word, and by sound doctrine both exhorts and convinces the gainsayer, he is termed teacher. These titles do not indicate different grades of office, but all describe one and the same office.
8-5. When a man is called to labor as a teaching elder, it belongs to his order, in addition to those functions he shares with all other elders, to feed the flock by reading, expounding and preaching the Word of God and to administer the Sacraments. As he is sent to declare the will of God to sinners, and to beseech them to be reconciled to God through Christ, he is termed ambassador. As he bears glad tidings of salvation to the ignorant and perishing, he is termed evangelist. As he stands to proclaim the Gospel, he is termed preacher. As he dispenses the manifold grace of God, and the ordinances instituted by Christ, he is termed steward of the mysteries of God.