To understand how to be righteous in the sight of God and be effective in doing what all Christians are meant to be doing which is to spread the gospel. We must understand the laws of God being written on the hearts of men. Unfortunately many Christians who have been born into the faith as second or third generation are best described as this verse.
Hebrews 5:11-13 ESV
About this we have much to say, and it is hard to explain, since you have become dull of hearing.  For though by this time you ought to be teachers, you need someone to teach you again the basic principles of the oracles of God. You need milk, not solid food,  for everyone who lives on milk is unskilled in the word of righteousness, since he is a child.
Thinking on the first Pentecost. At the beginning they were full of power of the Holy spirit. They had nothing but the spirit of god, no money, nothing holding them down. No government protecting their rights to worship. No programs.
Acts 3:2-9 ESV
And a man lame from birth was being carried, whom they laid daily at the gate of the temple that is called the Beautiful Gate to ask alms of those entering the temple.  Seeing Peter and John about to go into the temple, he asked to receive alms.  And Peter directed his gaze at him, as did John, and said, “Look at us.”  And he fixed his attention on them, expecting to receive something from them.  But Peter said, “I have no silver and gold, but what I do have I give to you. In the name of Jesus Christ of Nazareth, rise up and walk!”  And he took him by the right hand and raised him up, and immediately his feet and ankles were made strong.  And leaping up, he stood and began to walk, and entered the temple with them, walking and leaping and praising God.  And all the people saw him walking and praising God,
Now we have all this and now we are void of God’s power.
As far as adultery goes conservatives, liberals, and churches are swimming in it. The bible definition of how God intended man to be was this it is not good for a man to be alone, Genesis. Man is to become one with his own wife, not wives. Not second or third wives. Every single example of polygamy in the bible is one of broken or hard marriages that lead to hardships and consequences later on. Jesus said to divorce for anything else but adultery in the marriage is adultery. When we partake in this we are as guilty as anyone else. Yes we have forgiveness in repentance but only if our hearts are in repentance and love towards those who still need that same forgiveness.
As far as the law of our hearts are concerned according to the bible, there is no true union but that between a man and woman in God’s eyes. Man however trying to appease the law in his heart by remarriage, aren’t guiltless of God’s Laws. By condemning anyone else for breaking his laws we condemn ourselves. As far as homosexuality is concerned, there is no binding union according to the bible. Therefore whether or not there is a ceremony or certification there is none according to the bible. I would point out that by judging those who partake in such things only condemn themselves by the biblical laws they broke. Paul was echoing the words of Jesus, Matthew 18:35 ESV
So also my heavenly Father will do to every one of you, if you do not forgive your brother from your heart.”
It is very interesting to me that while we like to separate others from ourselves, God always talks to those who continue to live in sin like we are still in the church. Why is this interesting to me? Because of this.
Matthew 13:24-30 ESV
He put another parable before them, saying, “The kingdom of heaven may be compared to a man who sowed good seed in his field,  but while his men were sleeping, his enemy came and sowed weeds among the wheat and went away.  So when the plants came up and bore grain, then the weeds appeared also.  And the servants of the master of the house came and said to him, ‘Master, did you not sow good seed in your field? How then does it have weeds?’  He said to them, ‘An enemy has done this.’ So the servants said to him, ‘Then do you want us to go and gather them?’  But he said, ‘No, lest in gathering the weeds you root up the wheat along with them.  Let both grow together until the harvest, and at harvest time I will tell the reapers, “Gather the weeds first and bind them in bundles to be burned, but gather the wheat into my barn.”‘”
Until the end of the harvest the good is there. Within the church we have both good and bad seed planted. Until the end there is still hope for the good seed. Also he said this to those to in the church not the unbelievers
Revelation 3:19-22 ESV
Those whom I love, I reprove and discipline, so be zealous and repent.  Behold, I stand at the door and knock. If anyone hears my voice and opens the door, I will come in to him and eat with him, and he with me.  The one who conquers, I will grant him to sit with me on my throne, as I also conquered and sat down with my Father on his throne.  He who has an ear, let him hear what the Spirit says to the churches.'”
If you treat people like your enemy, forever they will be your enemies. If you treat people like your brother or sister, perhaps your enemy will become your family. If not then your reward is still in heaven.