I found this in chapter 17 of Tertullian's Apology:
"The object of our worship is the One God, He who by His commanding word, His arranging wisdom, His mighty power, brought forth from nothing this entire mass of our world, with all its array of elements, bodies, spirits, for the glory of His majesty...The eye cannot see Him, though He is (spiritually) visible. He is incomprehensible, though in grace He is manifested. He is beyond our utmost thought, though our human faculties conceive of Him. He is therefore equally real and great...He is presented to our minds in His transcendent greatness, as at once known and unknown. And this is the crowning guilt of men, that they will not recognize One, of whom they cannot possibly be ignorant. Would you have the proof from the works of His hands, so numerous and so great, which both contain you and sustain you, which minister at once to your enjoyment, and strike you with awe; or would you rather have it from the testimony of the soul itself? Though under the oppressive bondage of the body, though led astray by depraving customs, though enervated by lusts and passions, though in slavery to false gods; yet, whenever the soul comes to itself, as out of a surfeit, or a sleep, or a sickness, and attains something of its natural soundness, it speaks of God; using no other word, because this is the peculiar name of the true God."
Peace,
Kirk and Sarah