Suffering

You must understand the simple fact that no-one can harm another according to his whims fancies. Sufferings come to you under the law of cause-and-effect; and the person who causes the suffering is only agent of this Law.
Everyone carries within him the imprints of his Karma. When a person does something wrong, something sinful, he has to bear the consequences of such actions. Nature has to bring out and erase the imprints of sins and thus purify him. This process of purification may sometimes be achieved by the individual's own action that may result in pain or suffering to him. At other times the pain or suffering may come to him through the action of others.

Whatever be the agency through which pain comes, you must not forget that the cause was in your own deeds and that the suffering that falls to your lot is meant to purify you.
The individual who causes pain to you is only an instrument in the hands of Nature. His own Karma has made him do harm to you. He will have to bear the consequences of his actions sooner or later, but that is not your concern.
What you must constantly remember is that nothing in the Universe can bring you suffering unless your actions warrant it.
- Shri Vethathiri Maharishi