I've written before on the idea that Salvationists need to be 'bilingual' - we need to be able to speak the language of the social service sector as well as that of Christian theology. I guess it could be argued that too few of us are fluent in either language, let alone capable of skillfully crossing both. However there is an additional challenge.
All language is rooted in implicit connections between words and related concepts, sometimes called frames. When we try talking to secular people about the Christian motivations for our social work, we not only have to overcome a language barrier but more critically a shift in frames. We may feel that we have theological answers, but these are only relevant if someone is asking theological questions - they have to be in the same frame to begin with.
Before this sounds too hopeless, let me suggest that I think we share a common frame around helping people in need. This is a critical starting point and initially our actions will speak much louder than words. As we learn each others language and begin to navigate unfamiliar frames, a common commitment to the vulnerable and marginalised can serve as a solid basis for further dialogue.