10) And magic is a Greater sin. Thus Allah (A.J) says:
﴾and certainly they know that he who bought it (the magic) should have no share of good in the hereafter and evil was the price for which they sold their souls; had they but known this﴿
The Holy Qur’an (Surah 2, The Cow (Surah Baqarah), verse102).
11) Among the Greater Sins is Adultery (fornication). Allah says in the Holy Qur’an:
﴾And they who do not call upon another god with Allah and do not slay a soul which Allah has forbidden except in the requirements of justice, and (who) do not commit fornication. And he who does this shall find a requital of sin. The punishment shall be doubled to him on the Day of Resurrection, and he shall abide therein in abasement.﴿
The Holy Qur’an (Surah 25, The Criterion (Surah Furqan), verses68-69).
12) One of the Greater Sins is taking a false oath. Allah says about it.
﴾(As for) those who take a small price for the covenant of Allah and their own oaths-Surely they shall have no portion in the hereafter, and Allah will not speak to them, nor will He look upon them on the day of resurrection nor will He purify them, and they shall have a painful chastisement.﴿
The Holy Qur’an (Surah 3, The family of Imran (Surah Aale Imran), verse76).
13) Among the sins which are specifically graded as Greater is a sin of "betrayal of trust, or to act unfaithfully. Allah the Greatest has informed thus:
﴾And it is not attributable that he should act unfaithfully; and he who acts unfaithfully shall bring that in respect of which he has acted unfaithfully on the day of resurrection; then shall every soul be paid back fully what it has earned, and they shall not be dealt unjustly. Is then he who follows the pleasure of Allah like him who has made himself deserving of displeasure from Allah, and his abode is Hell; and it is an evil destination.﴿
The Holy Qur’an (Surah 3, The family of Imran (Surah Aale Imran), verse161-162).
14) Failure to pay the Zakat is a Greater sin. Allah says regarding it:
﴾And (as for) those who hoard up gold and silver and do not spend it in Allah’s ways, announce to them a painful chastisement.﴿
The Holy Qur’an (Surah 9, The repentance (Surah Tauba), verse34).
15) To bear a false witness is also a Greater sin. Allah says
﴾...and avoid false words.﴿
The Holy Qur’an (Surah 22, The Pilgrimage (Surah Hajj), verse30).
16) Do not conceal evidence as it is a Greater sin. Allah says:
﴾...and do not conceal testimony and whoever conceals it, his heart is surely sinful; and Allah knows what you do.﴿
The Holy Qur’an (Surah 2, The Cow (Surah Baqarah), verse283).
17) Drinking of wine is a Greater sin. As it is prohibited by Allah in the following verse of the Holy Qur’an:
﴾They ask you about intoxicants and games of chance. Say: In both of them there is great sin and means of profit for men, and their sin is greater than their profit.﴿
The Holy Qur’an (Surah 2, The Cow (Surah Baqarah), verse219).
18) To wilfully avoid the prayers is a Greater sin.
19) The failure to perform any obligatory religious act is a Greater sin. The Holy Prophet (PBUH) says:
"One who wilfully avoids the prayers is away from the protection of Allah and His Messenger."
20) Breaking an oath is also a Greater sin. Allah has stated:
﴾Who break the covenant of Allah after its confirmation and cut as under what Allah has ordered to be joined, (that is mutual relationships) and make mischief in the land; these it is that are the losers.﴿
The Holy Qur’an (Surah 2, The Cow (Surah Baqarah), verse27).
21) To break ties with the relatives is one of the Greater Sins. In the Qur’anic verse quoted below, Allah says,
﴾And cut asunder what Allah has ordained......﴿
The Holy Qur’an (Surah 13, The Thunder (Surah Raad), verse25).
When Imam Jafar Sadiq (A.S) concluded his hadith the narrator, Umroo bin Abeed rose up and while going out stopped and said: "Certainly, one who does not follow the guidance of the Imams (A.S) and gives his own opinion is doomed." It means that those who refuse to follow the Imams (A.S) are on the wrong path.
* The book named: GREATER SINS. By Al-Haaj Sayyed Abdul Hussein Dastghaib Shirazi (r.a)