What's the difference between a brother and a priest?

Answer: 

A brother is a layman who commits himself to Christ by the vows of poverty, chastity, and obedience, who lives in religious community, and who works in nearly any job: teacher, electrician, cook, lawyer, mechanic, artist, etc. A priest's distinctive role is as minister of the sacraments: celebrating Eucharist, Baptism, Penance, proclaiming the Word of God and serving the people.