..."If we analyse the conception of pleasure, we find that we cannot have any feeling of pleasure if we have no conception of pain. Similarly if we have no conception of pain, we could have no conception of pleasure. We can only know what one feeling is, by comparing it with the other feeling we had before and also knowing the difference. And then if we are going to enjoy pleasure throughout eternity, we must have some sort of conception of pain, otherwise we cannot enjoy pleasure throughout eternity. It is for that reason that those who believe in an eternity, will have to believe in eternal hell fire. The underlying truth of it is that we cannot enjoy the one without experiencing the other.
In the gross descriptions of hell and heaven, we find that there is a glass wall, separating hell from heaven, through which the souls, enjoying celestial pleasures, can see the others suffering and can compare and enjoy their pleasures; otherwise there is no enjoyment. It 78would be truly impossible for us to enjoy that pleasure if we enjoy that all the time and have no break. Now if we like music and hear music day and night without doing anything else, music would be a pleasure no more to us and within six hours we would be tired of it. If we see one colour all the time, it would no longer be a colour. If we can go to heaven and remain there throughout eternity, it would be no pleasure at all. Now under all these conditions we cannot find that eternal life in heaven with a finer body in the meaning of immortality, nor the enjoyment of celestial pleasures of the same kind without having any condition for comparison, is the meaning of immortality..."
The relative importance of Evil-
Life Beyond Death- Swami Abhedananda- quote