1) The connection between zina (adultery) and poverty: Poverty is of two types: poverty of hand and poverty of heart. Zina may take away and erase the blessing of wealth, because it is ingratitude for the blessing and using it to disobey the One who granted the blessing. Then the person is tested with poverty of heart because of his weakness of faith. So his heart starts to seek that which it does not have and he is not given patience to bear it, and this is an ongoing punishment. (From Sharh al-Shihaab)
2) The believer should not allow his tongue to become accustomed to cursing and swearing: “The believer is not one who slanders, curses or utters foul or obscene speech.” (al-Tirmidhi; classed as saheeh by al-Albaani) Whoever indulges in a lot of something will make it a habit.
3) Extravagance means overstepping the mark in spending money. Waste means spending it inappropriately, which is worse then extravagence. Hence Allah says: “Verily, the spendthrifts are brothjers of the Shayaateen (devils). And the Shaytaan (Satan) is ever ungrateful to his Lord.” [al-Isra’ 17:26-7 – intrpr. of meaning]
4) Looking at haraam pictures leads to nothing but loss, pain and sorrow. The poet spoke the truth when he said: “When you give free rein to your eyes, this will cause great pain to your heart. You will see what you cannot have, and you will feel frustration because you do not have some of what you see.” All that is gained is the anger of Allah, wasting time and money, and tormenting oneself.
5) The envier harms himself in three ways: 1) He earns sin because hasad is haraam; 2) It is bad etiquette before Allah, because what hasad really means is hating Allah’s blessing His slaves, and objecting to what Allah does; 3) He suffers because of worry and distress.
6) Hasad (destructive envy) is of varying degrees: 1) When a person wants a blessing to be taken away from his Muslim brother, even if it does not come to himself. Rather he does not like Allah to bless anyone else; 2) Where he wants the blessing to be taken away from someone else because he wants it, in the hope that he will get it; 3) Where he wishes he had the same blessing as someone else, without wanting it to be taken from the other person. This is permissible and is not called hasad, rather it is called ghibtah.
7) Keep it secret. The Prophet (peace be upon him) said: “A conversation in a gathering is a trust.” If a person is entrusted to a conversation on the basis that it is a secret, then it is not permissible for him to spread it. Similarly, if spreading it will resulth in harm tp his Muslim brother, it is not permitted. “There should be neither harming nor reciprocating harm.” And if spreading it will result in scandal for a sinning Muslim brother whose sin has been concealed by Allah, it is not permissible to spread it.
8) Harmless lies? ‘Abd-Allah ibn Mas’ood said: Lying is not appropriate whether in earnest or in jest. Recite if you wish: “O you who believe! Fear Allah, and be with those who are true (in words and deeds).” [al-Tawbah 9:119 – intrpr. of meaning] Then he said: Do you find any concession allowing that to anyone?
9) What crosses the mind …. : If someone thinks a thought of zina, stealing, consuming intoxicants and so on, but he does not do anything, then he is forgiven for that and he does not incur sin thereby. The Prophet (peace be upon him) said: “Allah has forgiven my ummah for what crosses their minds, so long as they do not speak of it or act upon it.”
10) The one who sells an item in which there is a fault must point out its faults, whether he is selling it to a Muslim or not, otherwise he will be decieving and sinning. The Messenger of Allah (peace be upon him) said: “The two parties to a transaction have the option (of cancelling it) until they part. If they are honest and disclose any defects, their transaction will be blessed, but if they lie and conceal defects the blessing will be erased.” (al-Bukhaari, Muslim)