There are two internals in man, one beneath and the other above. While man lives in the world he is in the internal which is beneath and from which he thinks, for it is natural. This may be called for the sake of distinction the interior. But the internal that is above is that into which man comes after death when he enters heaven. All angels of heaven are in this internal, for it is spiritual. This internal is opened to the man who shuns evils as sins; but it is kept closed to the man who does not shun evils as sins. This internal is kept closed to the man who does not shun evils as sins, because the interior, that is, the natural internal, until man has been purified from sins, is hell; and so long as there is hell there heaven cannot be opened; but as soon as hell has been set aside it is opened. But let it be noted that in the measure in which the spiritual internal and heaven are opened to man, the natural internal is purified from the hell that is there. This is not done at once, but successively by degrees. All this makes clear that man from himself is hell, and that man is made a heaven by the Lord, consequently that he is snatched out of hell by the Lord, and raised up into heaven to the Lord, not without means but through means; and these means are the commandments just mentioned, by which the Lord leads him who wishes to be led. (A.E., n. 940.) When the spiritual internal is opened, and through it communication with heaven and conjunction with the Lord are granted, enlightenment takes place with man. He is enlightened especially when he reads the Word, because the Lord is in the Word, and the Word is Divine truth, and Divine truth is light to angels. Man is enlightened in the rational, for this directly underlies the spiritual internal, and receives light from heaven and transfers it into the natural when it is purified from evils, filling it with the knowledges of truth and good, and adapting to them the knowledges (scientiae) that are from world, for the sake of proof and agreement. Thus man has a rational, and thus he has an understanding. He who believes that man has a rational and an understanding before his natural has been purified from evils is deceived, for the understanding is seeing truths of the church from the light of heaven; and the light of heaven does not flow into those not purified. And as the understanding is perfected, the falsities of religion and of ignorance and all fallacies are dispersed. (A.E., n. 941.)