1. Duty toward God
2. Duty toward members (of both the local church and the church universal)
3. Duty toward the lost
So then, worship is the primary responsibility. Included in that is the preaching of the Word, prayer, singing. As a natural consequence, the building up of the body encourages the worship of God. Finally, evangelizing the lost is the means whereby God adds souls to the body. Keeping these priorities in mind should help to answer the question of the details. By the way, these priorities similarly apply to other spheres of government as well, keeping God as the top priorities, but the other responsibilities vary according to the people involved.
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