Major Sins (68 & 69)

68) Deception and Evil Schemes

Allah, Most High say, {But the plotting of evil will hem in only the authors thereof} (Fatir: 43)
The Prophet (pbuh) said, "Plotting and duplicity are in the Hell-Fire.”1

"A deceiver, a miser and he who reminds recipients of his charity to them will not enter paradise.” Allah the Almighty says about the hypocrites: {They seek to deceive Allah, but it is Allah who deceive them.} (An-Nisa: 142)

Al-Wahidi said, "They will be treated in the manner they treated others: they will be shown the light as the believers but when they approach the Sirat (a bridge on fire) the light diminishes and they will be left in darkness.
The Prophet (pbuh) said, "The people of Hell-Fire are five" and mentioned a man who disaffects one's wife or property from him day and night.”2

69) Spying on the Muslims and Revealing their Weaknesses

Included in this subject is the hadith of Hatib Ibn Abi Balta’ah (1) (who sent a secret letter telling of the Muslims military plans to his relatives in Mecca in hopes that they would not get hurt), 'Umar (Allah be well pleased with him) wanted to kill him for what he had done, but the Prophet (pbuh) forbade 'Umar to, as Hatib had fought at Badr (and by accepting Hatib's excuse, left nothing for any Muslim to criticize.3

If someone's spying entails undermining Islam and its people, or the killing of captives, enslavement, or plundering of the Muslims, or anything of the like, then he is one of those who strive for corruption in the land, destroying tillage and offspring, and he is subject to death, and deserves the torment (of Hell-Fire), may Allah save us from it, Anyone who spies necessarily knows that if ordinary talebearing is a major sin, spy's carrying information is far more abominable and heinous, May Allah save us from that for He is the Ever-Clement?

1 Reported by Ai-Hakim and A1-Baihaqi.
2 Reported by Muslim.
3 This story ismantioned in the Sahih of AI-Bukhri.