The Prophet would divide (his time) equally between his wives and said: "O Allah! This is my division in what I have control over, so do not punish me for what You have control over which I do not have control over."  

أَنَّ النَّبِيَّ ﷺ كَانَ يَقْسِمُ بَيْنَ نِسَائِهِ فَيَعْدِلُ وَيَقُولُ اللَّهُمَّ هَذِهِ قِسْمَتِي فِيمَا أَمْلِكُ فَلاَ تَلُمْنِي فِيمَا تَمْلِكُ وَلاَ أَمْلِكُ  

The Messenger of Allah said: "When a man has two wives and he is not just between them, he will come on the Day of Judgment with one side drooping."  

عَنِ النَّبِيِّ ﷺ قَالَ إِذَا كَانَ عِنْدَ الرَّجُلِ امْرَأَتَانِ فَلَمْ يَعْدِلْ بَيْنَهُمَا جَاءَ يَوْمَ الْقِيَامَةِ وَشِقُّهُ سَاقِطٌ