The Facebook message of the invitation reads: “The victims of the attack are our brothers and sisters. Their experiences are ours as well. Just one day after the Athens Pride Parade we have to mourn for the loss of young people who fought like we do for visibility and pride”.
The organizers call on all groups and citizens to take a stand. They also clarify that lighting candles is not associated with any religion and that the event is open to anyone who wishes to end homophobia and prejudice.   
You can find the Facebook event here. More than 1K people have already expressed their intention to attend.