These are the views of speculative thinkers which we may adopt, but they cannot tell us what is the content of the terms _wisdom_ and _right conduct_. Not having been privileged to receive the sacred Law, which is the source of all wisdom and the origin of rectitude, they cannot tell us in concrete fashion just what a man must know and what he must do in order to raise his soul to the highest degree possible for it to attain. And if they were to tell us what they understand by wisdom and right conduct, we should not listen to them. Our authority is the Bible, and we must test the views of the philosophers by the teaching of the Bible. If we do this we find authority in Scripture also for belief in the immortality of the soul. Thus if we study carefully the expressions used of the various creations in the first chapter of Genesis, we notice that in some cases the divine command is expressed by the phrase, "Let there be...," followed by the name of the thing to be created; and the execution of the command is expressed by the words, "And there was...," the name of the created object being repeated; or the phrase may be simply, "And it was so," without naming the object. In other cases the expression "Let there be" is not used, nor the corresponding "And there was." This variation in expression is not accidental. It is deliberate and must be understood. Upon a careful examination we cannot fail to see that where the expression "Let there be" is used, the object so created exists in this world permanently and without change. Thus, "Let there be light" (Gen. i, 3). If in addition we have the corresponding expression, "And there was," in connection with the same object and followed by its name, it means that the object will continue its everlasting existence in the next world also. Hence, "And there was light" (_ib._). In the creation of the firmament and the luminaries we have the expression, "Let there be"; the corresponding expression at the end is in each case not, "And there was...," but, "And it was so." This signifies that in this world, as long as it lasts, the firmament and luminaries are permanent and without change; but they will have no continuance in the next world. In the creation of the sublunar world we do not find the phrase, "Let there be," at all, but such expressions as, "Let the waters be gathered together" (_ib._ 9), "Let the earth produce grass" (_ib._ 11), and so on. This means that these things change their forms and have no permanent existence in this world. The phrase, "And it was so," recording the realization of the divine command, signifies that they do not exist at all in the next world.