To-day's festival is called the Festival of the Trinity. What is the doctrine of the Trinity? For it certainly behooves every one to understand what is meant thereby, and this doctrine is held by all the Christian churches. Whosoever believes it, becomes a member of the Church. Whoever rejects it, ceases to belong to the Christian Church, and becomes a heretic.
Scripture tells us on the one hand that God is one, that there are not three Gods, but one God; on the other hand, that the Father is God, that our blessed Lord Jesus, the Son, is God, that the Holy Ghost is God, each person being a perfect God, yet so joined, each to each, that they constitute one invisible God. We are taught that these three persons are uncreated, incomprehensible, eternal, almighty, equal in glory, majesty, and power. None is before, none after, none greater or less than another; they are coeternal and coequal.
That is the plain teaching of God's holy Word. The Father, the Son, and the Holy Ghost, each of them is God, and yet there are not three Gods, but one God. How these three persons are so united as to make up only one God, so that the persons are neither confounded, nor the substance divided, we are nowhere told in Scripture. On this, as with regard to many other matters, we must be content to be ignorant. That is a great hardship to the pride of the would-be wise. And so in the earliest ages men arose and strove against this doctrine of the Trinity. The first violent strife that agitated the early Christian Church was just on this point. Arius, a certain bishop, would not accept the simple statement of Scripture that Christ is God, in the same sense as the Father is God; he would make Him inferior in divine nature. A most fierce controversy was waged, which ended in Arius' being branded a heretic, as, indeed, he was, and the true faith being only the more clearly confessed in the creeds of the Church, called the Athanasian and the Nicene Creed.
Does this doctrine sound strange and hard to believe to the carnal understanding? Let those who would be wise come forward, and prove their right to be admitted into the mystery of heaven, by showing that they have fully mastered the lesser mysteries of earth. Let them tell us, for instance, why the needle of the compass always turns toward the north. Perhaps they will say, Because it is in its nature to do so. But that is no answer. Our question is, _Why_ does the needle so turn? What secret and invisible hand twists it around and causes it to point always the same way? Or, if this be too puzzling a question, perhaps these wise people who think it so great a hardship that they are not permitted to understand God, may tell us a little about themselves. They can perhaps teach us how it comes to pass that the blood keeps flowing unceasingly through our veins, without our being aware of it, except when we are in a high fever. We grow tired with labor or with exercise, we tire even with doing nothing, but the blood never ceases in its flow; from the hour of our birth, day and night, summer and winter, year after year, it keeps on with its silent round, never stopping, till it stops once for all. How, I ask, can these things be? No answer. And this is not the only matter by any means. There is, for instance, sleep. Who does not sleep? One-third of our lifetime is spent in sleep. Who can say what this is? And if you cannot,--and no one can,--let those who know nothing about the how and the why in so many, yea, in most of earthly matters, not be so very much surprised that they cannot understand the existence of that invisible, that eternal, that infinite Spirit whom we call God.