Selection from Apocalypse Explained ~ Emanuel Swedenborg
[The] will is formed out of goods, and from these man has love and affection ... the understanding is formed out of truths therefrom, and from these man has intelligence and wisdom. And as truths are nothing but forms of good, it follows that the understanding is nothing but a form of its will. The only difference is that the understanding sees and the will feels. From this it is clear that such as man's will of good is, such is his understanding of truth, or what is the same, such as man's love is such is his intelligence. From this it is evident that although the will and the understanding are two faculties of life, still they act as one, and for this reason these two faculties of life are called one mind. This relates to the natural man.In the spiritual man also there are a will and an understanding, but much more perfect; and these are also called one mind. This therefore is the spiritual mind, and the other is the natural mind. But these are such with the man whose spiritual mind has been opened and formed; but it is altogether different with the man whose spiritual mind is closed, and only the natural mind opened.
The same can be said of charity and faith as has been said of the will and understanding; for the will is the subject and receptacle of charity as it is the subject and receptacle of good, and the understanding is the subject and receptacle of faith because it is the subject and receptacle of truth; for charity derives all that it is from good, and faith derives all that it is from truth; and this is why it is said the good of charity, and the truth of faith. From this it follows that charity and faith act as one, like will and understanding; and that such as the charity is such is the faith. But these are in the natural mind; but in the spiritual mind there is the love of good in place of charity, and the perception of truth in place of faith.
That spiritual love, which is charity, produces faith, can be seen merely from this, that man after death, who is then called a spirit, is nothing but an affection which is of love, and his thought is from that; consequently the whole angelic heaven is arranged into societies according to the varieties of affections; and everyone in heaven, in whatever society he may be, thinks from his affection; and therefore it is affection, which is love, that produces faith, and such faith as the affection is; for faith is nothing but thinking that a thing is so in truth, while affection means love in its continuation. But at the present day man in the world does not know that his thought is from affection and according to it, for the reason that he sees his thought but does not see his affection, and as his thought is his affection in a visible form therefore he knows no otherwise than that thought is the whole mind of man. It was otherwise of old with the ancients where the churches were. Because these knew that love produces all things of thought, therefore charity (which is the affection of knowing truths, of understanding them, and of willing them, and thus of becoming wise) was made by them the chief means of salvation. And as that affection makes one with faith they did not know what faith is.
From this it is evident not only how faith is formed with man but also that faith never can produce charity; but charity, which is spiritual love, forms faith as an effigy of itself, and in it presents an image of itself; and for this reason the nature of faith is known from charity and its goods, which are good works, as the nature of a tree is known from its fruit. By a "tree," however, faith is not meant, but man in respect to his life; while its leaves signify the truths through which there is faith, and its fruits signify goods of life, which are the goods of charity. Besides these arcana respecting the formation of faith by the Lord by means of charity there are innumerable others; but still it is the Lord who works all these arcana, while man knows nothing about it; all that man needs to do is to learn truths from the Word and to live according to them.
(Apocalypse Explained 790:9-14)