Selection from Arcana Cœlestia ~ Emanuel Swedenborg
Doctrine concerning good is the Doctrine of Charity
Doctrine concerning truth is the Doctrine of Faith.
In general, there is only one doctrine, namely, the doctrine of charity, for all things of faith look to charity. Between charity and faith there is no other difference than that between willing what is good and thinking what is good (for he who wills what is good also thinks what is good), thus than that between the will and the understanding.They who reflect, know that the will is one thing and the understanding another. This is also known in the learned world, and it plainly appears with those who will evil and yet from thought speak well; from all which it is evident to everyone that the will is one thing, and the understanding another; and thus that the human mind is distinguished into two parts, which do not make a one. Yet man was so created that these two parts should constitute one mind; nor should there be any other distinction (to speak by comparison) than such as there is between a flame and the light from it (love to the Lord and charity toward the neighbor being like the flame, and all perception and thought being like the light from it); thus love and charity should be the all of the perception and thought, that is should be in each and all things of them. Perception or thought concerning the quality of love and charity is that which is called faith.
But as the human race began to will what is evil, to hate the neighbor, and to exercise revenges and cruelties, insomuch that that part of the mind which is called the will was altogether destroyed, men began to make a distinction between charity and faith, and to refer to faith all the doctrinal matters that were of their religion, and call them by the single term faith; and at length they went so far as to say that they could be saved by faith alone - by which they meant their doctrinal things - provided they merely believed these, no matter how they might live. Thus was charity separated from faith, which is then nothing else whatever (to speak by comparison) than a kind of light without flame, such as is wont to be the light of the sun in time of winter, which is cold and icy, insomuch that the vegetation of the earth grows torpid and dies; whereas faith from charity is like the light in the time of spring and summer, by which all things germinate and bloom.
This may also be known from the fact that love and charity are celestial flame, and that faith is the spiritual light therefrom. In this manner also do they present themselves to perception and sight in the other life; for there the Lord's celestial manifests itself before the angels by a flaming radiance like that of the sun, and the Lord's spiritual by the light from this radiance, by which also angels and spirits are affected as to their interiors, in accordance with the life of love and charity that appertains to them. This is the source in the other life of joys and happinesses with all their varieties. And all this shows how the case is with the statement that faith alone saves.
(Arcana Cœlestia 2230)