The study of every thing that stands connected with the death of Christ, whether it be in the types of the ceremonial law, the predictions of the prophets, the narratives of the Gospels, the doctrines of the epistles, or the sublime vision of the Apocalypse, this is the food of the soul, the manna from heaven, the bread of life. This is "meat indeed" and "drink indeed."

... (because) the only real danger that exists is men himself. He is the great danger and we are pityfully unaware of it. We know nothing of men. Far too little ...

Carl Gustav Jung, 1959 in an interview with John Freeman ( youtube watch?v=2AMu-G51yTY 38:04)

Knowledge is the food of the soul.

Knowledge is the food of the soul; and we must take care, my friend, that the Sophist does not deceive us when he praises what he sells, like the dealers wholesale or retail who sell the food of the body; for they praise indiscriminately all their goods, without knowing what are really beneficial or hurtful.

Who feeds a hungry animal feeds his own soul.

Feed the soul, starve the ego.

The man who will live above his present circumstances is in great danger of living in a little time much beneath them; or as the Italian proverb runs, "The man who lives by hope, will die by hunger."

Translation: The soul of man is nourished by learning, as the body is by food.

Now, what is food? Why is food so important? Why do human beings need so much of it - three times a day, every day, year after year? Why do they live on food instead of on something else? Wouldn't it be better if human beings didn't need food at all? Wouldn't it be better if they could live on air, for instance? Get stronger and bigger by breathing sea air, or the air of the mountains, or the forests, or the meadows, or the vineyards and orchards, the wheat fields, the gardens all over the world? Wouldn't that be a better way for men to stay alive?
(spoken by 10-year-old Aram Saroyan)

Is it not strange that sheep's guts could hail souls out of men's bodies?

And what, Socrates, is the food of the soul? Surely, I said, knowledge is the food of the soul.