I have just been playing that lovely 'hunt the hymn' game ready for the service a week on Sunday at which we will be rededicating and recomissioning those of our folk directly involved in outreach activities. Naively, I decided to use the subject indexes in Mission Praise and Songs of Fellowship and the contents pages in Baptist Praise and Worship and (shock horror) Baptist Hymnbook to try to find things that fit the theme of mission. Just as well as I had a few ideas up front - it's not a popular heading in newer books.
Mission Praise had an 'evangelism and mission' section in its thematic indexes which included some great mission hymns and songs; the dreaded green book has a section on 'witness and worldwide mission' - including a few treasures that have fallen from favour over the years. The least bad heading in BPW was 'witnessing' and SOF has 'proclamation and evangelism,' though again, each of these include some superb material. Only Common Ground has a thematic entry specifcially titled 'mission.'
What strikes me most is that categorising of hymns and songs seems to have shifted a lot in the last few decades to be very much centred on 'me and Jesus' (or even, in some cases, separate themed sections for 'me and God the Father', 'me and Jesus' and 'me and the Holy Spirit') - yes I know the grammar is bad, but I think it often so ego-centric that the bad grammar is the more honest ordering. The work and purpose of the church has somehow got itself relegated to section D4 or some such.
It will be interesting to see how the next generation of hymn resources (I guess they may not be real, paper books by then) goes about categorising its songs and what that actually says about how the church sees itself.
In the meantime, it is looking as though it will be to golden oldies that I turn, such as this from the Overseas Mission Fellowship: -
Facing a task unfinished,
That drives us to our knees,
A need that, undiminished,
Rebukes our slothful ease.
We who rejoice to know Thee,
Renew before Thy throne
The solemn pledge we owe Thee,
To go and make Thee known.
...
O Father who sustained them,
O Spirit who inspired,
Saviour, whose love constrained them
To toil with zeal untired
From cowardice defend us,
From lethargy awake!
Forth on thine errands send us,
To labour for Thy sake.
Frank Houghton (c) Overseas Missionary Fellowship
And in case you want to use it, it is in Mission Praise Combined (and so, presumably, Complete with or without supplement)