The tenets of both Hyper-Calvinism and Arminianism maintain that unregenerate sinners ought not to be required to perform that which they are incapable of doing. Therefore, from the Hyper-Calvinist perspective, preachers must not offer the gospel indiscriminately. They need to first look for those who have the inner warrant to come to Christ for their salvation and then preach to them exclusively, whereas the Arminians maintains that sinners ought not to be required to respond positively to the gospel unless they have the ability to do so.
However, for Fuller this dilemma existed because they did not differentiate the distinctions between natural and moral ability. The natural ability was the basis upon which “heathens” have a duty to respond in faith and repentance. The fact that they have moral inability to do so does not in any way invalidate this duty. If the unregenerate “heathens” rejected the message of the gospel, they would be choosing to do so in accordance with their own desires. Their volition simply reveals who they are, as individuals—whether or not they are reprobate or elect—should they respond positively. In either case, the unregenerate are making choices without outside constraints other than those they themselves impose; that is, their own moral inability. Fuller therefore states, “No man in the world, in his right senses, ever thought of excusing another in unreasonable hatred towards him, merely because his propensities that way were so strong that he could not overcome them. And why should we think of excusing ourselves in our unreasonable and abominable enmity to God”?
Moreover, since God used the preaching of missionaries to the unregenerate as his means of salvation, in Fuller’s thought, he was both logical and coherent in illuminating Carey to thus ensure the obligation of missionaries to offer the gospel to all.
As its secretary, Fuller’s contribution to the formation of the BMS was pre-eminent. The perception of him as “the Rope Holder” of Carey’s ministry in India is also an accurate portrait, but perhaps it was in his capacities as theologian and apologist that Fuller made his most vital contribution to the Protestant missionary movement.
[Excerpt from “A Mainspring of Missionary Thought: Andrew Fuller on Natural and Moral Inability,” American Baptist Quarterly 25, no. 4 (winter, 2006): 348-349.]