By laying on hands at ordination, the bishops and other priests ask the Holy Spirit to indwell the person being ordained. The purpose of this is to set the person apart for the ministry that he is about to enter and to provide him with a sacred character.
Ordination is the religious ceremony in which a person becomes a deacon or minister, thereby gaining the ability to minister on behalf of the church. The actual ordination consists of two parts: laying on of hands and the prayer of consecration. Bishops must be present at ordination because they are a part of the apostolic tradition established by Jesus in the New Testament.