1 Corinthians 14:12

'So also you, since you are zealous of spirits, seek that you may abound to the edifying of the church.'

Now he turns to apply his words directly to his hearers. He recognises that they are 'zealous of spirits'. 'Spirits' must have in mind their own spirits, through whom the Spirit operates. Compare the 'spirits of the prophets' (1 Corinthians 14:32), Paul's own 'spirit' (1 Corinthians 14:14), 'the spirits of the prophets' in 1 John 4:1. Thus he must mean 'zealous of inner spirits that are active spiritually', presumably, in context, in the use of spiritual gifts. In that case, he says, seek to abound with a view to edifying the church. In that way they will be manifesting love and giving exhortation and instruction which benefits all.