574. All reason shows that man must be regenerated, for he is born into evils of every kind derived from his parents; and these evils have their seat in his natural man, which of itself is diametrically opposed to the spiritual man. Nevertheless man is born for heaven; although he does not enter heaven unless he becomes spiritual, and he can become spiritual only by means of regeneration. From this it follows of necessity that the natural man with its lusts must be subdued, subjugated, and inverted, and that otherwise man cannot approach a single step toward heaven, but sinks deeper and deeper into hell. Who cannot see this, if he believes that he has been born into evils of every kind and acknowledges the existence and contrariety of good and evil, and believes in a life after death, a hell and a heaven, and that evil is what constitutes hell and good is what constitutes heaven? Viewed in himself the natural man in no way differs in his nature from the nature of beasts. Like them he is wild; but it is as to his will that he is such; in understanding he differs from beasts, in that the understanding can be elevated above the lusts of the will, and not only see but also moderate them; and for this reason man is able to think from understanding, and speak from thought, which beasts cannot do. What man is by birth, and what he would be if not regenerated, can be seen from fierce animals of every kind; that he would be a tiger, a panther, a leopard, a wild hog, a scorpion, a tarantula, a viper, a crocodile, and so on; consequently if he were not transformed by regeneration into a sheep, what would he be but a devil among devils in hell? And in that state, if not restrained by civil laws, would not men from innate ferocity, rush upon one another and slaughter each other, and plunder each other even of the last scrap of clothing? How many are there of the human race who are not born satyrs and priapi or four-footed lizards; and who among these, if not regenerated, does not become an ape? External morality is required, for the sake of covering up their internals; and it does that.