"Again, the societies have taught us from every pulpit that every Christian should be at heart a missionary, on the unshakable ground that the spirit of Christ is given to all Christians, and that the spirit given is the spirit which longs for and strives after the salvation of all men in Christ……The preacher, no doubt, expected a reaction in the form of support for his society, and no doubt it generally took that form, but there is no reason why it should take that form. There is nothing in the teaching to convince anyone that to express his missionary zeal he need support, or belong to, any other society than the Church to which he already belongs. It is not necessary, though it may be convenient, to support any special society in order to do missionary work….He does not cease to be a Christian and a member of a missionary body because he does not add to the order of the Church the more elaborate and precise order of some society organization. The only reason why men have not so acted more often is because they have been obsessed with the idea that a man to express his missionary zeal properly must be a member of some other body within the church and that church membership is not sufficient.
Many before now have thought that if they were to express their zeal freely outside the limits and restrictions of a special missionary society, they must go outside the Church itself. But that is absurd. The multiplication of societies, which, viewed as a missionary organization for the attainment of a common object, is wasteful, has at least kept before us the truth that men can work outside the societies without working outside the Church."
- Roland Allen
From his book The Spontaneous Expansion of the Church