Allah commands that the property of the orphans be surrendered to them in full when they reach the age of adolescence, and He forbids using or confiscating any part of it. So He said;
وَلاَ تَتَبَدَّلُواْ الْخَبِيثَ بِالطَّيِّبِ
(and do not exchange (your) bad things for (their) good ones;) Sa`id bin Al-Musayyib and Az-Zuhri commented, "Do not substitute a weak animal of yours for a fat animal (of the orphans)." Ibrahim An-Nakha`i and Ad-Dahhak commented, "Do not give something of bad quality for something of good quality." As-Suddi said, "One of them (caretakers of orphans) would take a fat sheep from the orphan's property and put in its place, a weak sheep of his, saying, `A sheep for a sheep.' He would also take a good Dirham and exchange it for a fake Dirham, saying, `A Dirham for a Dirham."' Allah's statement,
وَلاَ تَأْكُلُواْ أَمْوَلَهُمْ إِلَى أَمْوَلِكُمْ
(and devour not their substance to your substance.) means, do not mix them together so that you eat up both, as Mujahid, Sa`id bin Jubayr, Muqatil bin Hayyan, As-Suddi and Sufyan bin Hassin stated. Allah said,
إِنَّهُ كَانَ حُوباً كَبِيراً
(Surely, this is a great sin. ), a major and substantial sin, according to Ibn `Abbas. This was also reported from Mujahid, `Ikrimah, Sa`id bin Jubayr, Al-Hasan, Ibn Sirin, Qatadah, Muqatil bin Hayyan, Ad-Dahhak, Abu Malik, Zayd bin Aslam and Abu Sinan. The meaning above is: adding their property to your property is a grave sin and a major mistake, so avoid it.
Allah said,
وَإِنْ خِفْتُمْ أَلاَّ تُقْسِطُواْ فِى الْيَتَـمَى فَانكِحُواْ مَا طَابَ لَكُمْ مِّنَ النِّسَآءِ مَثْنَى
(And if you fear that you shall not be able to deal justly with the orphan girls, then marry (other) women of your choice, two) Allah commands, when one of you is the caretaker of a female orphan and he fears that he might not give her a dowry that is suitable for women of her status, he should marry other women, who are plenty as Allah has not restricted him. Al-Bukhari recorded that `A'ishah said, "A man was taking care of a female orphan and he married her, although he did not desire to marry her. That girl's money was mixed with his, and he was keeping her portion from her. Afterwards, this Ayah was revealed about his case;
وَإِنْ خِفْتُمْ أَلاَّ تُقْسِطُواْ
(If you fear that you shall not be able to deal justly)" Al-Bukhari recorded that `Urwah bin Az-Zubayr said that he asked `A'ishah about the meaning of the statement of Allah,
وَإِنْ خِفْتُمْ أَلاَّ تُقْسِطُواْ فِى الْيَتَـمَى
(If you fear that you shall not be able to deal justly with the orphan girls.) She said, "O my nephew! This is about the orphan girl who lives with her guardian and shares his property. Her wealth and beauty may tempt him to marry her without giving her an adequate dowry which might have been given by another suitor. So, such guardians were forbidden to marry such orphan girls unless they treated them justly and gave them the most suitable dowry; otherwise they were ordered to marry woman besides them." `A'ishah further said, "After that verse, the people again asked the Messenger of Allah ﷺ (about marriage with orphan girls), so Allah revealed the Ayah,
وَيَسْتَفْتُونَكَ فِى النِّسَآءِ
(They ask your instruction concerning the women..) 4:127." She said, "Allah's statement in this Ayah,
وَتَرْغَبُونَ أَن تَنكِحُوهُنَّ
(yet whom you desire to marry) 4:127 refers to the guardian who does not desire to marry an orphan girl under his supervision because she is neither wealthy nor beautiful. The guardians were forbidden to marry their orphan girls possessing property and beauty without being just to them, as they generally refrain from marrying them (when they are neither beautiful nor wealthy)."
Allah's statement,
مَثْنَى وَثُلَـثَ وَرُبَاعَ
(two or three, or four), means, marry as many women as you like, other than the orphan girls, two, three or four. We should mention that Allah's statement in another Ayah,
جَاعِلِ الْمَلَـئِكَةِ رُسُلاً أُوْلِى أَجْنِحَةٍ مَّثْنَى وَثُلَـثَ وَرُبَـعَ
(Who made the angels messengers with wings, - two or three or four) 35:1, does not mean that other angels do not have more than four wings, as there are proofs that some angels do have more wings. Yet, men are prohibited from marrying more than four wives, as the Ayah decrees, since the Ayah specifies what men are allowed of wives, as Ibn `Abbas and the majority of scholars stated. If it were allowed for them to have more than four wives, the Ayah would have mentioned it. Imam Ahmad recorded that Salim said that his father said that Ghilan bin Salamah Ath-Thaqafi had ten wives when he became Muslim, and the Prophet said to him, "Choose any four of them (and divorce the rest)." During the reign of `Umar, Ghilan divorced his remaining wives and divided his money between his children. When `Umar heard news of this, he said to Ghilan, "I think that the devil has conveyed to your heart the news of your imminent death, from what the devil hears during his eavesdropping. It may as well be that you will not remain alive but for a little longer. By Allah! You will take back your wives and your money, or I will take possession of this all and will order that your grave be stoned as is the case with the grave of Abu Righal (from Thamud, who was saved from their fate because he was in the Sacred Area. But, when he left it, he was tormented like they were)." Ash-Shafi`i, At-Tirmidhi, Ibn Majah, Ad-Daraqutni and Al-Bayhaqi collected this Hadith up to the Prophet's statement, "Choose any four of them." Only Ahmad collected the full version of this Hadith. Therefore, had it been allowed for men to marry more than four women at the same time, the Prophet would have allowed Ghilan to keep more than four of his wives since they all embraced Islam with him. When the Prophet commanded him to keep just four of them and divorce the rest, this indicated that men are not allowed to keep more than four wives at a time under any circumstances. If this is the case concerning those who already had more than four wives upon embracing Islam, then this ruling applies even more so to marrying more than four.
Allah's statement,
فَإِنْ خِفْتُمْ أَلاَّ تَعْدِلُواْ فَوَحِدَةً أَوْ مَا مَلَكَتْ أَيْمَـنُكُمْ
(But if you fear that you will not be able to deal justly (with them), then only one or what your right hands possess.) The Ayah commands, if you fear that you will not be able to do justice between your wives by marrying more than one, then marry only one wife, or satisfy yourself with only female captives, for it is not obligatory to treat them equally, rather it is recommended. So if one does so, that is good, and if not, there is no harm on him. In another Ayah, Allah said,
وَلَن تَسْتَطِيعُواْ أَن تَعْدِلُواْ بَيْنَ النِّسَآءِ وَلَوْ حَرَصْتُمْ
(You will never be able to do perfect justice between wives even if it is your ardent desire) 4:129. Allah said,
ذلِكَ أَدْنَى أَلاَّ تَعُولُواْ
(That is nearer to prevent you from Ta`ulu), meaning, from doing injustice. Ibn Abi Hatim, Ibn Marduwyah and Abu Hatim Ibn Hibban, in his Sahih, recorded that `A'ishah said that, the Prophet said that the Ayah,
ذلِكَ أَدْنَى أَلاَّ تَعُولُواْ
(That is nearer to prevent you from Ta`ulu), means, from doing injustice. However, Ibn Abi Hatim said that his father said that this Hadith to the Prophet is a mistake, for it should be attributed to `A'ishah not the Prophet . Ibn Abi Hatim reported from Ibn `Abbas, `A'ishah, Mujahid, `Ikrimah, Al-Hasan, Abu Malik, Abu Razin, An-Nakha`i, Ash-Sha`bi, Ad-Dahhak, `Ata' Al-Khurasani, Qatadah, As-Suddi and Muqatil bin Hayyan that Ta`ulu means to deviate from justice.
`Ali bin Abi Talhah reported Ibn `Abbas saying, Nihlah, in Allah's statement,
وَءَاتُواْ النِّسَآءَ صَدُقَـتِهِنَّ نِحْلَةً
(And give to the women (whom you marry) their Saduqat Nihlah) refers to the dowry. Muhammad bin Ishaq narrated from Az-Zuhri that `Urwah said that `A'ishah said that `Nihlah' means `obligatory'. Muqatil, Qatadah and Ibn Jurayj said, `Nihlah' means `obligatory' Ibn Jurayj added: `specified.' Ibn Zayd said, "In Arabic, Nihlah, refers to what is necessary. So Allah is commanding: Do not marry unless you give your wife something that is her right. No person after the Prophet is allowed to marry a woman except with the required dowry, nor by giving false promises about the dowry intended." Therefore, the man is required to pay a dowry to his wife with a good heart, just as he gives a gift with a good heart. If the wife gives him part or all of that dowry with a good heart, her husband is allowed to take it, as it is lawful for him in this case. This is why Allah said afterwards,
فَإِن طِبْنَ لَكُمْ عَن شَىْءٍ مِّنْهُ نَفْساً فَكُلُوهُ هَنِيئاً مَّرِيئاً
(But if they, of their own pleasure, remit any part of it to you, take it, and enjoy it without fear of any harm.)