With the greatest clearness, accordingly, the Word has spoken respecting Himself by Hosea: “I am your Instructor.” Now piety is instruction, being the learning of the service of God, and training in the knowledge of the truth, and right guidance which leads to heaven. And the word “instruction” is employed variously. For there is the instruction of him who is led and learns, and that of him who leads and teaches; and there is, thirdly, the guidance itself; and fourthly, what is taught, as the commandments enjoined.