Parachurch organizations exist for different reasons. Usually they aim to meet needs that go beyond the scope of a single congregation; (para = along side). Are they scriptural or not? Should Christians support them or give time to work in them? These are good questions considering the proliferation of such organizations in modern times.
As far as can be learned from the book of Acts, all ministries for Christians were sponsored by believers working under the guidance and blessing of the local church in which they fellowshipped. There is no direct record of so called “parachurch organizations” as are found in such abundance today. We may think of the plan to reach distant lands undertaken by Paul and Barnabas or the work to feed widows in Jerusalem. These needs were addressed by the church that became aware of them. The Lord moved in hearts to meet needs, yet no society or organization outside the local church was formed. No board was set up having representatives from several churches. Yet would it have been wrong to do so?
Christian liberty allows for innovations that do not compromise Biblical .principles, although such structures often do. One need not look hard for examples. Consider the organizations that exist simply because the local church, that could be doing the work, is asleep. Also think of the churches in which Christians are not being equipped for the work of the ministry (Eph. 4:11-12) because a hired professional cares for the bulk of the church’s worship and leadership functions. Wanting significant involvement, and unable to find it in the church because they are only “lay people,” many turn to organizations that exist to “serve the church.” Often referred to as an “arm of the church,” they can be a regrettable evidence that the heart of the church’s ministry is unavailable to the people. On the surface, becoming involved in a parachurch organization keeps everyone happy. The organization is pleased to have help; the people who become involved can rise to the top and have a real piece of the action; the minister of the church is satisfied because his people find involvement, render service, and yet pose no threat to his position. Sometimes they even bring financial gains into the church. However, these things work against clear Biblical principles for the church, and sincere believers ought to question involvement in them. Bodies with extra arms are not healthy.
On the other hand, there are organizations that meet needs that could probably not be met by individual churches unless they were extremely large. Developed not because the church was inactive, but in order to enable churches to better function yet in no way controlling them. Think of Christian schools and colleges, hospitals, retirement homes and even missionary aviation organizations. It’s hard to measure what the church owes to such works as they provide services that might otherwise be unavailable. As an example, assemblies have long depended on missionary service organizations to help them send out, support, and care for returning missionaries. Although they make look similar, they are very different from mission boards that dictate support amounts and procedures, and control the placing and labors of the missionary.
How can a Christian “prove all things and hold fast to that which is good?” Check to see if the organization in question exerts pressure or tries to control one or more local churches. See if financial matters are open, available, and accountability is thorough. If you are considering involvement, be sure you have first done your part in your own local fellowship so that the elders can heartily endorse your involvement in something outside the church. If these things check out, it may be a good avenue of involvement. Helping in a worthy organization may be one way to serve the body of Christ from behind the scenes.