1. A sound mind, and one which does not expose its possessor to danger, and is devoted to piety and the love of truth, will eagerly meditate upon those things which God has placed within the power of mankind, and has subjected to our knowledge, and will make advancement in [acquaintance with] them, rendering the knowledge of them easy to him by means of daily study. These things are such as fall [plainly] under our observation, and are clearly and unambiguously in express terms set forth in the Sacred Scriptures. And therefore the parables ought not to be adapted to ambiguous expressions. For, if this be not done, both he who explains them will do so without danger, and the parables will receive a like interpretation from all, and the body of truth remains entire, with a harmonious adaptation of its members, and without any collision [of its several parts]. But to apply expressions which are not clear or evident to interpretations of the parables, such as every one discovers for himself as inclination leads him, [is absurd.] For in this way no one will possess the rule of truth; but in accordance with the number of persons who explain the parables will be found the various systems of truth, in mutual opposition to each other, and setting forth antagonistic doctrines, like the questions current among the Gentile philosophers.