Hebrews 13.4 commands marriage must be honored among all. The Scriptures command Christians to honor marriage.
When the Bible refers to marriage it means the union of one man to one woman who have covenanted before God and His people to honor, love and remain with one another for the raising of godly children and to glorify God on earth as long as they both shall live.
It never means the union of two men or two women for God repeatedly declares this behavior an abomination to Him for He Himself instituted marriage when He created the first man and the first woman.
Some who call themselves Christian have voiced support for the modern ‘equality’ of marriage movement promulgated by the homosexual community. These supporters seek to please people more than please God for they ignore God’s clear will and teaching by their complete disregard for His written record for humanity.
Sexual immorality is a major theme of the Bible where God has repeatedly condemned and prohibited His people from engaging in it like the rest of humanity who ignores God.
Among the sexually immoral acts God condemns besides homosexuality are adultery and fornication. This is why God commands marriage be honored by His people and is the only place where God blesses the sexual union of two people.
All sexual activity outside the marriage union is immoral before the Judge of all humanity Who will not take into consideration the opinion of men on that Day when He judges each of us in accordance with our obedience to His commands.