Hebrews 13: 4 rules out what, but what question might arise? The things that a sincere Christian needs to avoid are not limited to what the Bible specifically prohibits.
وَهذَا مَا يَتَبَيَّنُ لَنَا مِمَّا كَانَ قَدْ أَوْضَحَهُ بُولُسُ فِي رِسَالَةٍ أُخْرَى .‏