[1 of 1] Swedenborg (1688-1772, Sweden): primary subject "Illness, spiritual causes of" (search under Inner Life/Death, Suffering)": source "Spiritual Experiences, vol.4": detail "Section 4592"
All sicknesses with mankind occur from no other source than from the spiritual world, most of them being no other than lusts, such as immoderation in regard to various vices and overindulgence in them, such as various sensual pleasures, promiscuity, and anxiety over future things to come. These are the genuine causes of all sicknesses. Nor is death itself from any other source than by reason of sin. These things contaminate the blood, and when this happens, they obstruct and choke up the very small vessels, for which reason sicknesses break out. This is why sicknesses interact with those auras from hell. If people had lived in a state of goodness, they would decline to the end of old age, and then, when the body could no longer respond to the needs of the inner person, then they would pass over from the earthly body, without sickness.