1 So let a man think of us as Christ’s servants, and stewards of God’s mysteries. 2 Here, moreover, it is required of stewards, that they be found faithful.
Have you ever thought why from us is required faithfulness? (verse 2) The answer is in verse 1, because we are stewards of mysteries. The main thing which is required from us it not to tell to much (keep secrets)! It is faithfulness.
For God all things are simple. But after studying these two verses I think that for God is even simpler to transform a faithful stupid into a clever person than to transform a not faithful clever person into a faithful person.
So I conclude from 1Cor. 4:1-2 that if we have faithfulness to not say what we should not to say, then God will give us the rest (intellect, power, etc.)
Who is truly faithful indeed cannot be very stupid, because to be faithful is to differentiate what to do and what not to do (accordingly will of God), and who can differentiate these things in not stupid. It is a lie of Devil about stupid faithful persons. If one is faithful, he is already not stupid.
I deem that to be faithful is enough, because in this case God will give us all the rest gifts.