"...he saw two men kissing each other in front of his wife and kid and he got very angry."

But it has nothing to do with religion, according to the killer's father.  Who supports the Taliban and thinks god will punish the gays.  

Religion, making everything worse since always.

Prescient, in hindsight.  From a March interview.  "Milo: 'For gays, what distinction between Islam and terrorism?'"

LGBT in Islam - Wikipedia, the free encyclopedia: "Extreme prejudice remains, both socially and legally, in much of the Islamic world against people who engage in homosexual acts. In Afghanistan, Brunei, Iran, Mauritania, Nigeria, Saudi Arabia, Sudan, United Arab Emirates and Yemen, homosexual activity carries the death penalty. In others, such as Algeria, Maldives, Malaysia, Qatar, Somalia and Syria, it is illegal...  

In 2013, the Pew Research Center conducted a study on the global acceptance of homosexuality and found a widespread rejection of homosexuality in many nations that are predominantly Muslim. In some countries, views were actually becoming more conservative among younger people...  A 2007 survey of British Muslims showed that 61% believe homosexuality should be illegal, with up to 71% of young British Muslims holding this belief. A later Gallup poll in 2009 showed that none of the 500 British Muslims polled believed homosexuality to be "morally acceptable". 

77 countries where homosexuality is illegal | 76 CRIMES

What Does Islam Say About Gay Marriage? Muslim Scholar Explains | Variety: "The issue of gay marriage in America is a tough one for Muslims. On one hand, it’s nigh impossible to construct an argument by which sexual contact between men, let alone anal sex, is considered permissible in God’s eyes."

The Left Chose Islam Over Gays. Now 100 People Are Dead Or Maimed In Orlando - Breitbart: "According to the murderer’s father, his son became angry after he saw two men kissing in the street. “This had nothing to do with religion,” said the father, Seddique Mateen. “He saw two men kissing each other in front of his wife and kid and he got very angry” — as if that was some kind of excuse. That same father is on record defending the Taliban."

Omar Mateen got 'very angry' seeing two men kissing, father tells NBC - LA Times: "Omar Mateen's father, Mir Seddique, spoke to NBC News about the shooting . "This had nothing to do with religion," he told the network. "We were in downtown Miami, Bayside, people were playing music. And he saw two men kissing each other in front of his wife and kid and he got very angry," Seddique told NBC. "They were kissing each other and touching each other and he said, 'Look at that. In front of my son they are doing that.' And then we were in the men's bathroom and men were kissing each other.""

Orlando shooting gunman Omar Mateen father Seddique Mateen a Taliban supporter says God will punish gays - CBS News: "The Orland gay club gunman's father has well-known anti-American views and is an ideological supporter of the Afghan Taliban. A new message posted by the father on Facebook early Monday morning also makes it clear he could have passed anti-homosexual views onto his son. Seddique Mir Mateen, father of Orlando gunman Omar Mateen, who died in a shootout with police after killing at least 49 people early Sunday morning, regularly attended Friday prayers at a Florida mosque with his son... The elder Mateen says he was saddened by his son's actions during the Muslim holy month of Ramadan. He then adds: "God will punish those involved in homosexuality..."

The Left Chose Islam Over Gays. Now 100 People Are Dead Or Maimed In Orlando - Breitbart: "Omar Mateen wasn’t just a homophobe, by the way. He was also a misogynist – a real one, not someone who offends feminists on Twitter – who repeatedly beat his ex-wife while they were married. Of course, as we saw in Cologne six months ago, this sort of behaviour is also the norm in Muslim cultures. Needless to say, the Left is silent on the subject."

On the other hand...

LGBT in Islam - Wikipedia, the free encyclopedia: "However, in 20 out of 57 Muslim-majority nations same-sex intercourse is not forbidden by law."

Which means in about 1/3 being gay isn't illegal.  That's something, I guess.