(23:1-7) Successful indeed are the believers; who are reverent during their Contact Prayers (Salat). And they avoid vain talk. And they give their obligatory charity (Zakat). And they maintain their chastity. Only with their spouses, or those who are rightfully theirs, do they have sexual relations; they are not to be blamed. Those who transgress these limits are the transgressors.
2:235] You commit no sin by announcing your engagement to the women, or keeping it secret. GOD knows that you will think about them. Do not meet them secretly, unless you have something righteous to discuss. Do not consummate the marriage until their interim is fulfilled. You should know that GOD knows your innermost thoughts, and observe Him. You should know that GOD is Forgiver, Clement.
[24:31] And tell the believing women to subdue their eyes, and maintain their chastity. They shall not reveal any parts of their bodies, except that which is necessary. They shall cover their chests, and shall not relax this code in the presence of other than their husbands, their fathers, the fathers of their husbands, their sons, the sons of their husbands, their brothers, the sons of their brothers, the sons of their sisters, other women, the male servants or employees whose sexual drive has been nullified, or the children who have not reached puberty. They shall not strike their feet when they walk in order to shake and reveal certain details of their bodies. All of you shall repent to GOD, O you believers that you may succeed.