1 Corinthians 14:5

'Now I would have you all speak with tongues, but rather that you should prophesy. And greater is he who prophesies than he who speaks with tongues, except he interpret, that the church may receive edifying.'

This preference for prophecy, Paul stresses, is not to demean tongues, for he would be happy for all to speak in tongues when praying privately, but rather because prophecy benefits all. He is not against tongues. He could wish that all might have the gift. But he would rather that they all prophesied. For this wish for something for all without it actually necessarily coming to fulfilment compare Numbers 11:29, which may well have been in Paul's mind (see also 1 Corinthians 7:7).

He then agrees that an exception can be made when an interpreter is present, for interpretation makes tongues edifying to all. An interpreter is someone with the supernatural gift to interpret the tongues and put them into the language known to the church members. Then the church members can also be benefited by tongues.

'Greater' in this case means 'of more value'. They are greater because what they do is more useful to all.