The wives of deacons are to be of the same high standard of character as their husbands, else they will undermine their husbands role in the church. They too are to be grave, dignified, not lightweight people.
The question arises, does this refer to women or to wives? The Greek has the same word for both. Our translation has decided it is ‘wives’ and I believe that is correct. It is about the wives of deacons. But it could be read differently. It could be read, ‘Even so must women be grave, not slanderers.’ What is the difference? Well, that would suggest you could have women deacons, and some exegetes – more particularly recent ones – have said that this is women deacons, and not wives of deacons. So we have to resolve it. One or two highly respected exegetes this century have plumped for the fact that women deacons are being referred to here. I think that one or two are influenced by their wrong notion of what a deacon is. For instance, one very fine exegete, who comes from the Christian Reformed churches in the United States, has a notion of a deacon as literally somebody who unlocks the door and sweeps the church. They have given all the authority to elders, and the deacon is merely a kind of ‘also ran’, a practical servant of the church. If an exegete has taken that position – which is a very weak position, and a minority position in the Reformed tradition – then his guard is down with regard to whether or not we should have woman deacons. After all, if the deacon is to have no authority, if the deacon is only to unlock and visit the sick for the sake of comfort and compassion and almsgiving, and to do practical things, then of course there would be no objection at all to there being deacons of either sex. But if the deacon has a ruling capacity, or has any authority or responsibility, then it would have to be a man, because that is the unvarying rule of the Scripture (1 Timothy 2:12). That would rule out the passage being translated as women or women deacons.
But there are other reasons also. Paul hasn't finished instructing on deacons, and continues in the next verse. It would be quite uncharacteristic of his method to interrupt himself with a single sentence of instruction on women deacons when he hasn't finished dealing with deacons who are male. So it is quite plain that he is referring to the wives of deacons. This is a passage about appointing officers in the church – elders and deacons – and if women deacons were referred to here, one of two things would be true. He would either be introducing a third office into the church, the office of woman deacon, with an undefined role and no practical example in the NT. (Phoebe, spoken of in Romans 16:1, is a servant of the church. Yes, the word is the feminine form of deacon, but the context must decide its meaning, and the word is used as a general term for a servant in several places in the NT without referring to a recognised office, Matthew 22:13; 23:11; John 2:5.) Or he would be wanting all that he has said about male deacons to be applied also to female deacons. The word used for deacon in the next verse and earlier in the chapter is a masculine word, and surely excludes any women deacons. Are we really to take all the qualifications of male deacons and apply them to women deacons also? This is obviously impossible, given the explicit requirement that they be the husbands of one wife. The New Testament does not teach the church to recognise a distinct office on the basis of such slender information. Then you look at the package of things which verse 11 requires: dignity, not slanderers, sober, which means literally here abstaining from wine. It's the strong ‘sober’ word. ‘Faithful in all things’, and those qualifications are of course the very things that you would expect from the apostle in discussing the wives of deacons. There is a non-authoritative package of qualities which fit in so admirably and so perfectly with the requirements of the wives of deacons. Dignified, not slanderers, sober in the sense no doubt of meaning self-controlled, and careful, discreet, and loyal in all things. Then in the very next verse, the very same phrase is used as was used for elders: ‘the husband of one wife’, and the same word which could be translated ‘woman’ or ‘wife’ is used there too, and can only refer to the deacon’s wives. Paul is not switching back and forth between these two meanings of the word without warning.