1. Religious worship is bound to its object, and cannot possibly be fixed in the hearts of men and the institutions of society, if the object be doubtful and fluctuating. False religion has often been set off with elaborate and gorgeous ceremonial, which has been kept up even after the performers had come to see in all that light and lustre a mere vain and unsubstantial show. Such were the rites of Roman polytheism, as enacted by augurs and pontiffs, the colleagues of Cicero and Cæsar. But though that worship was maintained, and even augmented, for political purposes, without a creed, yet never could it have arisen without some creed, however mistaken, earnestly held of old. A firm interior conviction is the starting-point of all outward worship. But if the modern living worshipper is without creed and conviction; if he be a scoffer at heart, or at least a doubter; what a hollow, horrid skeleton thing is his religion,--all the more horrid, the grander its dress! That is not worship, but mummery. 2. If then to worship God is a duty, as we have proved, it is a duty likewise to know God. This supposes that God is knowable, a fact which it does not lie within the province of this work to prove. To an unknown God, all the worship we could render would be to build Him an altar, without priest, prayer, or sacrifice, and so leave Him in His solitude. God is knowable by the _manifestation_ of His works (Rom. i. 19); and where He is pleased to speak, by the _revelation_ of His word. Apart from revelation--and, under a certain order of Providence, God might have left us without revelation--we should study our Creator as He is made manifest in the world around us, in the existence of perishable things, in the order of the universe, in the region of things eternally possible and knowable, in moral truths, in the mental life and conscience of man. Philosophy would be our guide in the search after God. Men with less leisure or ability for speculation would acquiesce in the pronouncements of philosophers on things divine; and, in the hypothesis which we are contemplating, Providence would doubtless arrange for the better agreement and harmony of philosophers among themselves. Their trumpet would not send forth so uncertain a blast, were that the instrument, in the counsels of God, whereby the whole duty of religion was to be regulated. As it is, we know better than philosophy could teach us: for God hath spoken in His Son. _Readings_.--_C. Gent_., i., 4; 1a 2æ, q. 91, art. 4, in corp. CHAPTER II. OF THE DUTY OF PRESERVING LIFE. SECTION I.--_Of Killing, Direct and Indirect_.