that the Prophet said: “The conditions most deserving to be fulfilled are those by means of which the private parts become permissible for you.” (Using translation from Ibn Mājah 1954)  

عَنِ النَّبِيِّ ﷺ قَالَ «إِنَّ أَحَقَّ الشُّرُوطِ أَنْ تُوفُوا بِهِ مَا اسْتَحْلَلْتُمْ بِهِ الْفُرُوجَ»