[Baqarah 2:234] And those among you who die leaving wives behind them, then such widows shall restrain themselves for four months and ten days; so when their term is completed, O guardians of such women, there is no sin on you in what the women may decide for themselves in accordance with Islamic law; and Allah is Well Aware of what you do.

[Baqarah 2:235] And there is no sin on you if you propose marriage to women while they are hidden from your view, or hide it in your hearts; Allah knows that you will now remember them, but do not make secret pacts with women except by decent words recognised by Islamic law; and do not consummate the marriage until the written command reaches its completion; know well that Allah knows what is in your hearts, therefore fear Him; and know well that Allah is Oft Forgiving, Most Forbearing.

Section 31

[Baqarah 2:236] There is no sin upon you if you divorce women while you have not touched them or appointed their bridal money; and give them some provision; the rich according to their means, and the poor according to their means; a fair provision according to custom; this is a duty upon the virtuous.

[Baqarah 2:237] If you divorce them before you have touched them and have appointed the bridal money, then payment of half of what is agreed is ordained unless the women forgo some of it, or he in whose hand is the marriage tie, pays more; and O men, your paying more is closer to piety; and do not forget the favours to each other; indeed Allah is seeing what you do.