An-Nisa' - 4:25

وَمَن لَّمْ يَسْتَطِعْ مِنكُمْ طَوْلاً أَن يَنكِحَ الْمُحْصَنَاتِ الْمُؤْمِنَاتِ فَمِن مِّا مَلَكَتْ أَيْمَانُكُم مِّن فَتَيَاتِكُمُ الْمُؤْمِنَاتِ وَاللّهُ أَعْلَمُ بِإِيمَانِكُمْ بَعْضُكُم مِّن بَعْضٍ فَانكِحُوهُنَّ بِإِذْنِ أَهْلِهِنَّ وَآتُوهُنَّ أُجُورَهُنَّ بِالْمَعْرُوفِ مُحْصَنَاتٍ غَيْرَ مُسَافِحَاتٍ وَلاَ مُتَّخِذَاتِ أَخْدَانٍ فَإِذَا أُحْصِنَّ فَإِنْ أَتَيْنَ بِفَاحِشَةٍ فَعَلَيْهِنَّ نِصْفُ مَا عَلَى الْمُحْصَنَاتِ مِنَ الْعَذَابِ ذَلِكَ لِمَنْ خَشِيَ الْعَنَتَ مِنْكُمْ وَأَن تَصْبِرُواْ خَيْرٌ لَّكُمْ وَاللّهُ غَفُورٌ رَّحِيمٌ
[4:25]
And whoever among you has not within his power ampleness of means to marry free believing women, then (he may marry) of those whom your right hands possess from among your believing maidens; and Allah knows best your faith: you are (sprung) the one from the other; so marry them with the permission of their masters, and give them their dowries justly, they being chaste, not fornicating, nor receiving paramours; and when they are taken in marriage, then if they are guilty of indecency, they shall suffer half the punishment which is (inflicted) upon free women. This is for him among you who fears falling into evil; and that you abstain is better for you, and Allah is Forgiving, Merciful.
If any of you have not the means wherewith to wed free believing women, they may wed believing girls from among those whom your right hands possess: And Allah hath full knowledge about your faith. Ye are one from another: Wed them with the leave of their owners, and give them their dowers, according to what is reasonable: They should be chaste, not lustful, nor taking paramours: when they are taken in wedlock, if they fall into shame, their punishment is half that for free women. This (permission) is for those among you who fear sin; but it is better for you that ye practise self-restraint. And Allah is Oft-forgiving, Most Merciful.
And whoso is not able to afford to marry free, believing women, let them marry from the believing maids whom your right hands possess. Allah knoweth best (concerning) your faith. Ye (proceed) one from another; so wed them by permission of their folk, and give unto them their portions in kindness, they being honest, not debauched nor of loose conduct. And if when they are honourably married they commit lewdness they shall incur the half of the punishment (prescribed) for free women (in that case). This is for him among you who feareth to commit sin. But to have patience would be better for you. Allah is Forgiving, Merciful.