Ed Stetzer interviews Keith & Kristyn Getty on Missional Hymns on Christianity Today:

Ed Stetzer: Tell us a little bit about how you put together the album in the first place. It’s very diverse.

Keith Getty: It all comes out of the Facing a Task Unfinished hymn, written by Frank Houghton, 1931, in the context of mass persecution in China. He writes this hymn as a call to 200 people to come preach. China, the context, was very anti-Christian, the minimizing of Christian rights, the murdering of Christians and indeed worldwide global recession.
A lot of things actually quite similar to our own times, but serious persecution.
So, he writes this hymn, sends it round as a call to missionary commitment. He gets a response of 204 people to go.

ES: Response to go as missionaries?

KG: That’s right. He understood—foundationally—that what we sing affects profoundly how we think and how we live. So deep Christian songs, sung by real believers to each other, breeds and helps contribute to breeding deep believers......

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