Vigils have taken place around the country to remember Aidan Moffitt and Michael Snee.
The two men were murdered in their homes in Co Sligo this week in suspected homophobic attacks.
Over 20 events were held across the country on Friday, with more vigils scheduled to take place on Saturday.
Commemorative events are also taking place in London.
Dublin Lord Mayor Alison Gilliland told those gathered outside the Dáil that diversity gives the capital its character.
"It breaks my heart that there is a very small minority of people who disrespect that diversity, and disrespect it to the extent that they are violent towards some of the people who live, work, and recreate in our city.
"For people like us here, showing our solidarity.... it is really, really important and it's incumbent on us all that we are pro-active, visible, strong allies.
Aidan Moffitt (left) and Michael Snee are seen in undated photos released by An Garda Sícohána"That we call out homophobic, biphobic and transphobic language and behaviours.
"We need to overtly stand with and stand for those who may feel fear in our city.
"Today we are showing that - but we also need to show that within our families, within our workplaces, within our places of learning and in our clubs and recreation facilities.
"It's up to us, all of us here, to be those allies: show our strength, and show our absolute disrespect for people who disrespect others."
A vigil being held outside Dáil Éireann in Dublin for Aidan Moffitt and Michael Snee. Picture by: James Wilson/Newstalk'Active undercurrent of prejudice'
James O'Hagan of LGBT Ireland says the gatherings send a strong message.
"The most significant statement being made here this evening, and at vigils all around the country, is yours.
"By coming here and standing in solidarity with the LGBTI+ community, you tell those who would discriminate against us that their actions are wholly unacceptable.
"This is a space to grieve, express your sorrow and anger, and also a space to acknowledge that the events of the past week - including the horrific attacks on Evan Somers in Dublin last weekend and a third victim of the attack in Sligo - have retriggered a fear of which all members of the LGBTI+ community have felt in our daily lives."
A vigil being held outside Dáil Éireann in Dublin for Aidan Moffitt and Michael Snee. Picture by: James Wilson/NewstalkHe says this has "tragically highlighted the active undercurrent of prejudice and discrimination against our community which still exists within Irish society".
He adds: "The problem of homophobia, biphobia and transphobia is all of Ireland's to solve.
"All members of the LGBTI+ community have the right to feel and be safe in our streets and online".
'Fear is a liar'
Businessman and National LGBT Federation board member Steve Jacques told the crowd Aidan and Michael will not be forgotten.
"We have come so far in Ireland, and in fact this country has becomes a safe haven for so many of our other LGBT people who come from dangerous places around the world.
"We are heartbroken that despite our progress, that we still see and experience harm and murder by others fueled by bigotry, fear and false beliefs.
"These experiences remind us again that fear is a liar - and it can cause unimaginable damage.
"But we are strong and we are defiant, and we stand in solidarity and together.
"It is always when you find us cornered or angry that we come out fighting, our passion for justice runs deep.
"We demand a safe Ireland where all people, including our own community, are free from harm and bigotry and hate.
"Michael and Aidan: we are not letting your death and your suffering go unnoticed, our rainbow community will remember you.
"Someone with no excuse whatsoever hurt you, and because they hurt you they hurt us".
