It is because of the sins that no one else knows about,and often God has corrected you about it but you excuse them just because what everyone else knows is that you are a great christian.
you can lie to everyone else but you can't lie to God.
If everyone else knows you are a good christian but you still keep hate,lust,self righteousness,pride etc you will not go with the Lord when He returns.
The only One you should really worry about is God,not other people.
Everyone else's opinion will not count when you stand before God.
So don't even make effort to get approval from people about your Christianity,seek God's approval.
Ask Him to search your life and show you anything that will make Him leave you behind when He comes.
Come before the searchlight of the Holyspirit now,and you wont be ashamed on that day.
I ll never forget these words that the Lord told me,"seek to be known by God,not by people."
If you do not have a personal relationship with Jesus Christ,you will not be ready when He comes.
Its about you and God,ONLY.
Do not let your eyes wander to everyone else around you,keep your eyes on Jesus.
The Apostle Peter wanted to do the same,and what did Jesus say to him?
John 21 :20-22 "Peter turned and saw that the disciple whom Jesus loved was following them. (This was the one who had leaned back against Jesus at the supper and had said, “Lord, who is going to betray you?”) When Peter saw him, he asked, “Lord, what about him?”
Jesus answered, “If I want him to remain alive until I return, what is that to you? You must follow me.”
Its the same answer He has for you even today,what is it to you what everyone else is doing?As for you,follow Him.
Do what Jesus wants,its all about you and Him.