This objection, so often repeated, never fails to astonish me. The majority of those who urge it, assert at the same time that God is incomprehensible, and that we cannot penetrate the secret of his nature. What then is this but to pretend to comprehend God? and by what right do they oppose his nature to his providence, if his nature is, to us, an impenetrable mystery? I refrain from reproaching them for their ambition; ambition is the privilege and the glory of man; but in retaining it, let them not overlook its legitimate limits. There is only this alternative: either man must cease to believe in God, because he cannot comprehend Him, or in effect admit his incomprehensibility, and still at the same time believe in Him. {30} He cannot pass and repass incessantly from one system to the other, now declaring God to be incomprehensible; now speaking of Him, of his nature and his attributes, as if He were within the province of human science. Great as is the question of Providence, the one I have here to consider is still greater, for it is the question of the very existence of God; and the fundamental inquiry is to know whether He exists, or does not exist. God is at once light and mystery: in intimate relation with man, and yet beyond the limits of his knowledge. I shall presently endeavour to mark the limit at which human knowledge stops, and indicate its proper sphere; but this I at once assume as certain: whoever, believing in God and speaking of Him as incomprehensible, yet persists in endeavouring to define Him scientifically, and seeks to penetrate the mystery, which he has yet admitted, is in great risk of destroying his own belief, and of setting God aside, which is one way of denying Him. {31}