845. The reason 'the fountains of the deep' means temptation as regards things of the will, and 'the floodgates of heaven' means temptation as regards those of the understanding, is that a person's will is what hell acts upon and not so much upon his understanding unless it has been immersed in evil desires that constitute the will. Evils within the will are what condemn a person and thrust him down to hell, and not so much falsities unless these are coupled with evils, in which case one follows the other. This becomes clear from the fact that so many people who are under the influence of falsities are nevertheless saved, as is the case with very many of the gentiles who have led lives of natural charity and of mercy, as well as Christians who have believed in simplicity of heart. Their very ignorance and simplicity excuse them, for innocence can reside within them.
[2] The situation is different with those who have confirmed themselves in falsities and have consequently pursued such a life of falsity that they reject and spurn all truth. Such a life must first of all be laid waste before any truth and so any good can be implanted. The situation is worse however with people who have so confirmed themselves in falsities resulting from evil desires that falsities and evil desires compose one life. These are the people who plunge into hell. This is the reason why temptation as regards things of the will is meant by 'the fountains of the deep', which are the hells, and temptation as regards those of the understanding by 'the floodgates of heaven', which are the clouds from which the rain falls.