Amash narrates from Imam Ja’far as-Sadiq (a.s.) and Fazl ibn Shazān who narrated from Imam ‘Ali Riďa (a.s.) that Qur’an has clearly mentioned chastisement for this sin and indicated the Shari punishment in Surah al-Mā’ida 33-34:
The punishment of those who wage war against Allah and His apostle and strive to make mischief in the land is only this, that they should be murdered or crucified or their hands and their feet should be cut off on opposite sides or they should be exiled; this shall be as a disgrace for them in this world, and in the hereafter they shall have a grievous chastisement,Except those who repent before you have them in your power; so know that Allah is Forgiving, Merciful. (Surah al-Mā’ida 5:33-34)
In Minhaj it is written that in the 6th year of Hijrah a group from Awniyah and Akal came to Holy Prophet (S) and accepted Islam and stayed on with him (S). But when the climate of Medina did not suit them, they fell sick. The Holy Prophet (S) was informed about their condition and he gave them permission to reside on the outskirts of Medina where camel milk was available in plenty at a place called “Jabalul Eier.” In this way they may stay there for some time and drink the milk and urine of camel to cure their disease and become healthy once more.
They left for the valley and stayed for some time and regained health. One day they hatched a conspiracy and stole 15 camels of the Holy Prophet (S) and returned to their tribe as Murtad (renegades). When the news reached Medina, Yasar, a servant of Holy Prophet (S) chased them with a few people and caught up with them. The two groups fought with each other. Yasar was captured, his hands and legs amputed, and eyes and tongue were pierced with thorns. At last he achieved martyrdom. When the Holy Prophet (S) came to know of this he sent Karbaz bin Jabir after them. He captured all of them and tied their hands and legs and brought them to the Holy Prophet (S). So Allah, the Most High, revealed His words: “The punishment of those who wage war…” (Surah al-Maidah, 5:33)