Tehillim 39 and Rabbi Nachman's segula from Breslov for an illness
Tehillim 39:9
“Cherpat naval al tesimeni” - (Do not hand me over to the contempt of the wicked).
After the weekly Torah portion of Vayechi, Rabbi Nachman said:
“At the third meal (seudah shlishit), a special remedy (segula) for an illness was revealed to me.
Take a little lye (chalk), and then three times as much soap by weight. Make a bath from them and bathe the child. Do this whenever the child begins to develop a fever.If this is not the final decree from Above concerning the child, it will be effective. But if it is a strict decree (chas veshalom), then it will not help”.
This illness is the result of the sin of the Golden Calf.
It may be difficult to understand this, because non-Jews also suffer from this illness. However, the Midrash teaches that non-Jews were not supposed to suffer from any illnesses (because their portion is the material world)—but then they would have humiliated the Jews, so G-d gave them the same illnesses as the Children of Israel.
“Do not hand me over to the contempt of the wicked.” (Tehillim 39:9)
This is a prayer that the wicked, too, should be afflicted with illness and pain, so that they cannot say: “You are being punished, but we are not.” According to this prayer, pain and illness came upon the non-Jews.
Another difficulty arises from the fact that this illness should have existed even before the sin of the Golden Calf. However, it was not a serious illness before then. According to physicians, this illness results from the food that the infant receives in its mother's womb. At first, however, it was not fatal as it is now. This is a result of the sin. The prophet's words allude to this to some extent:
“Even if you wash with neter (chalk, lye) and take much soap, your iniquity will remain a stain before Me”. (Jeremiah 2:22)
Rashi explains that this refers to the sin of the Golden Calf. Understand the miracles.”
(from the book “The Teachings of Rabbi Nachman of Breslov”)