Janet has suggested, as a topic for debate, we discuss whether the gospels and Acts are our primary texts for missiology. I've decided to respond in the negative and counter with, the New Testament is our primary text for missiology.
Yes, of course Acts is an obvious place to begin, as are the gospels. But I want to suggest that, if we truly affirm God as a missional God, then we need to be open to understanding all of God's word as missional.
The Old Testament
Indeed, if we affirm the YHWH of the Old Testament and the Father of the New Testament as the same, we should also be open to what the Old Testament has to say. The gospel of John suggests we be open to reading Genesis 1 more Christologically, and thus missiologically, and missionaries have long seen missional significance in the calling and sending forth of Abraham. And then we also have the story of Jonah, which deconstructs any suggestion that God cares only for those under the covenant. And then we also have the new covenant prophecies.
The New Testament
But, that being said, I am wary of over emphasizing the Old Testament. For just as Jesus is superior to Moses, so the New Testament is superior to the Old Testament, thus I think its important we keep a Christological focus when discussing mission. But given that all the New Testament was written in the aftermath of the resurrection and the sending of the apostles, I think all of the New Testament is pretty primary.
Revelation and the Letters
For instance, my missiology is heavily shaped by Revelation, by the vision of the extraordinary breaking into the ordinary world, by the vision of the conqueror as the vulnerable one, by the vision of a renewed earth and resurrected community, by the warning that the state is Babylon, by the call to come. Where is mission without vision?
My missiology is also heavily shaped by that extraordinary missionary, the apostle Paul. Where would my understanding of multicultural mission be without Paul's letter to the Galatians? And hey, are there any Calvinists out there? I expect you'd agree Romans shouldn't be underestimated in missiological / evangelistic importance either.
The Good News
Which brings us, of course, to the good news itself. The messiah spread the good news of the kingdom. The apostles spread the good news of the king. How can we understand how the two messages are one message without exploring how the gospels, Acts, letters and Revelation mutually interrelate?
So, without seeking to minimise the importance of the gospels and Acts for missiology, I say, without the letters and Revelation our reading of the gospels and Acts will be lopsided.