Man , as the husband , however , will not held responsible or accountable for things that he has no control over, such as love , affection and self comfort . Allah , the Almighty stated in the glorious Quran:
You will never be able to do perfect justice between wives even if it is your ardent desire, so do not incline too much to one of them (by giving her more of your time and provision) so as to leave the other hanging (i.e. neither divorced nor married). And if you do justice, and do all that is right and fear Allah by keeping away from all that is wrong, then Allah is Ever OftForgiving, Most Merciful. (Qur'an 4:129)
It is also reported that Allah’s Apostle , Peace be upon him used to divide things amongst his wives fairly and equally , then saying:
“ O Allah! This is the fair distribution that I can do best in accordance to my abilities . O Allah! Please blame me not for what you own and I do not own( i.e. the acts of the hear in terms of love and affection.”) This Hadith is reported by Abu Dawood , Tirmithe , Ibn Majah and Nasaiee.
However , if a husband preferred one wife over another in terms of spending the night with, based on the approval and acceptance of the other wife , then in such a case , there is no harm. That, in fact , was the case with Aishh and Swadah , two of his wives , may Allah be pleased with them , when Sawdah agreed to grant her night to Aisha, RAA toward the end of the life of the prophet, PBUH. Yet , when the prophet , PBUH , became very ill , he continuously asked : “ Where shall be tomorrow (i.e in whose house)?” All his wives agreed to let him stay at the house of Aisha m where he wanted to be until his death, PBUH.” This Hadith was reported by both Bukhari and Muslim.
http://www.arriyadh.com/En/Islam/LeftBar/Islamic-Ri/The-Right-of-the-Husband-and-The-Wif.doc_cvt.asp
