Divine Support of the Sick

(condensed from Ein Ayah, Shabbat 1:50)

Gemara: How do we know that the Divine Presence supports the ill? It is as it says, "Hashem will support him on his bed of anguish" (Tehillim 41:4).

Ein Ayah: Spiritual powers operate significantly to strengthen physical powers. Consolation, love, and all the emotions of integrity and altruism that enter man’s soul, calmly and with a good heart, strengthen not only his spiritual powers, but even his physical power. This is in line with the pasuk, "Fear of Hashem shall add days" (Mishlei 10:27). In contrast, jealousy, desires, seeking honor, anger, dissatisfaction, lack of faith, and ill-heartedness have a negative effect on the foundations of the body.
Hashem put into the human characteristic that at the time of his illness, when his physical side is on the verge of collapse and even death due to his overall weakness, his spiritual side has the tendency of being strengthened and positive powers are awakened. In place of a bad heart and a difficult spirit comes a heart of tender flesh. Holy images draw closer to his heart, even though they were distant from him when he was healthy because of the coarse materialism that ruled over him. Belief in Hashem and hope well up within him, and this provides him with support for his waning strength.
This is actually a case of Hashem supporting him, and this is indeed a purpose of the disease in the first place – to elevate man from his material lowness. A person is not extricated from disease without receiving atonement for sins, as is hinted in Iyov 33:25. This situation itself strengthens the powers of his spirit, and this added spiritual vigor strengthens his physical side, as the pasuk says, "A man’s spirit gives strength in his illness" (Mishlei 18:14).