Note 5 at 1Co 12:17: Here, Paul changed the analogy to illustrate how ridiculous it would be if there weren't different gifts in the body of Christ. We wouldn't like it if our bodies were one big eye or one big ear. Likewise, if every member of the body of Christ had the same gift, it would not be good. We need all the different gifts.

If the only gift that functioned in the church was the evangelist, how would the new converts ever grow without the pastor or teacher? If everyone had the gift of interpretation (see note 29 at 1Co 12:10), who would give the message in tongues (see note 28 at 1Co 12:10)? He was saying diversity is good if the different gifts can appreciate each other and work together.