The local church's purpose has to include an outward focus (mission), an inward focus (fellowship), but most importantly an upward focus (worship). Worship is the reason we were saved. It is the reason the church exists. It is the reason we do mission, to gain the Lord more people who worship Him. And it is the reason we do fellowship, in order to build up and encourage those who worship the Lord to continue worshipping the One who deserves our worship.