Tertullian

Since all things were made by the wisdom of God, it follows that when God made both the heaven and the earth in principio, that is to say "in the beginning," he made them in his wisdom. If, indeed, beginning had a material signification, the Scripture would not have informed us that God made so and so in principio, at the beginning, but rather ex principio, of the beginning, for he would not have created "in," but "of," matter. When wisdom, however, was referred to, it was quite right to say, "in the beginning."