It has been objected that there are multitudes in our own nation, and within our immediate spheres of action, who are as ignorant as the South-Sea savages, and that therefore we have work enough at home, without going into other countries. That there are thousands in our own land as far from God as possible, I readily grant, and that this ought to excite us to ten-fold diligence in our work, and in attempts to spread divine knowledge amongst them is a certain fact; but that it ought to supersede all attempts to spread the gospel in foreign parts seems to want proof. Our own countrymen have the means of grace, and may attend on the word preached if they choose it. They have the means of knowing the truth, and faithful ministers are placed in almost every part of the land, whose spheres of action might be much extended if their congregations were but more hearty and active in the cause: but with them the case is widely different, who have no Bible, no written language, (which many of them have not,) no ministers, no good civil government, nor any of those advantages which we have. Pity therefore, humanity, and much more Christianity, call loudly for every possible exertion to introduce the gospel amongst them.
William Carey, An Enquiry into the Obligations of Christians to Use Means for the Conversion of the Heathens (Kindle Edition)