Church diversity implies that some gifts are greater than others because of their usefulness to a greater number of people:
"Follow the way of love and eagerly desire spiritual gifts, especially the gift of prophecy. For anyone who speaks in a tongue does not speak to men but to God. Indeed, no one understands him; he utters mysteries with his spirit. But everyone who prophecies speaks to men for their strengthening, encouragement and comfort. He who speaks in a tongue edifies himself, but he who prophecies edifies the church. I would like every one of you to speak in tongues, but I would rather have you prophecy. He who prophecies is greater than one who speaks in tongues, unless he interprets, so that the church may be edified." I Corinthians 14:1-5 (NIV)