Nevertheless, concerning this subject much was reserved to be taught by the Mediator in his incarnate state, when the distinction of Persons in the Godhead and their official designations could be rendered plain by his visible personal acts, his verbal explanations, and the agency and gifts ascribed to the Holy Spirit. This was in accordance with the progress and analogy of revelation in other respects. Besides, we may well believe that there was originally, and during the Mosaic period, extreme difficulty in instructing men on those high themes concerning the invisible and spiritual, as may be inferred from the rooted and lasting propensity of the Israelites to visible symbols and material images, and from the limited prevalence of the clearer inculcations of the gospel down to the present day. Men did not and do not like to retain God in their knowledge. Hence the language of our Saviour in teaching the Divine unity and spirituality, and the distinction, offices and relations of the Persons of the Godhead. He taught that God is a Spirit, invisible, infinite, eternal, unchangeable; of himself, that he came out from God; came forth from the invisible to the visible world; that he should withdraw from the visible to the invisible, so as not to be seen; that he should afterwards visibly reäppear; that God the Father sent him; that the power which he exercised in his miracles was a divine attribute, and proved his divinity; that those who witnessed his miracles, witnessed the exercise of the power of the invisible Deity, which was the power of the Father who had sent him, as well as his own; and therefore they saw the Father in the same works in which they saw him; for in respect to their nature as divine, He and the Father were one. But even his disciples did not at first understand his meaning. "Philip saith unto him, Lord, show us the Father, and it sufficeth us. Jesus saith unto him, Have I been so long time with you, and yet hast thou not known _me_, Philip? He that hath seen _me_ hath seen the Father." That is, I act officially, exercising the power of the Deity, which is delegated to me by the Father. He who sees in my works a demonstration of my personality and divinity, sees at the same time in those works the only outward and visible demonstration that can be made to men of the personality and divinity of the Father. The power which I exercise is possessed by me in common with the Father, though personally and officially exercised by me. That power is a divine attribute, and in respect to it as an attribute, I and the Father are one.