And let us not be weary in well doing: for in due season we shall reap, if we faint not.

Galatians 6:9

John Newton, the former slave trader turned pastor-abolitionist and author of the hymn Amazing Grace, wrote this letter to a discouraged missionary friend serving the Lord in Australia:

I have not been disheartened by your apparent want of success.  I have been told that skillful gardeners will undertake to sow and raise a salad for dinner in a short time while the meat is roasting.  But no gardener can raise oaks with such expedition.  You are sent to New Holland, not to sow salad seeds, but to plant acorns; and your labor will not be lost, though the first appearances may be very small, and the progress very slow.  You are, I trust, planting for the next century.  I have a good hope that your oaks will one day spring up and flourish, and produce other acorns, which, in due time, will take root, and spread among the islands and nations in the Southern Oceans.

Taken from: Historical Records of New South Wales, Vol. 2 Appendix A, 445 by F.M. Bladen, Alexander Britton, and James Cook