This Marxian sentence, repeated to the point of boredom, is misinterpreted. In reality [Karl] Marx was a "religious" man.
Erich FrommThe sick individual finds himself at home with all other similarly sick individuals. The whole culture is geared to this kind of pathology. The result is that the average individual does not experience the separateness and isolation the fully schizophrenic person feels. He feels at ease among those who suffer from the same deformation; in fact, it is the fully sane person who feels isolated in the insane society - and he may suffer so much from the incapacity to communicate that it is he who may become psychotic.
Erich FrommMost people see the problem of love primarily as that of being loved, rather than that of loving, of one's capacity to love. Hence the problem to them is how to be loved, how to be lovable.
Erich FrommMan is the only animal who does not feel at home in nature, who can feel evicted from paradise, the only animal for whom his own existence is a problem that he has to solve and from which he cannot escape. He cannot go back to the prehuman state of harmony with nature, and he does not know where he will arrive if he goes forward. Man's existential contradiction results in a state of constant disequilibrium. This disequilibrium distinguishes him from the animal, which lives, as it were, in harmony with nature.
Erich Fromm