Just to play the devil's advocate:

In Koran God says that he has no partner and it's not even the job or Muhammad to convince people to be Muslim.

If God has no partner, it's not my job to interfere on people's sexuality. God can do it by himself.

If it's not even up to Mohammed to change people's mind about religion, why should it be to me to change people's mind?

They do whatever they want weather I like it or not, and God will deal with it, not me as neither me or anyone else is God's partner.

And also: where Im Koran is it saying that God disapproves Homosexuals? I read it many times and I didn't get impression it's a very bad thing 
 

 In islam if you want to change something you have to do it by yourself and god (allah) will help you and guide you all the prophets in islam did the same thing 

There is a word in our riligion called الاخذ بالاسباب it means doing the things that might give reasons to change

Our god (allah) won't help us if we stopped doing anything and just hope (allah) will do everything for us 

 In which Surah is this, in which exact phrase? I'll read it here.

I'm asking because religious people sometimes try to sell their culture or views as if it came from religious book, when it's clearly not in their scriptures.

I don't intended to offend you by asking the exact source