In the wake of the so-called 'Pantigate' controversy over homophobia comments made on RTE and a defamation settlement, Dr Martin said: "God never created anybody that he doesn't love."
Speaking to the Irish Independent, the senior cleric said this meant that "anybody who doesn't show love towards gay and lesbian people is insulting God. They are not just homophobic if they do that – they are actually Godophobic because God loves every one of those people".
Referring to the revelations made last week by TD Jerry Buttimer, that he was beaten, spat at, mocked and harassed because he was gay, Dr Martin expressed concern saying: "Certainly the sort of actions that we heard of this week of people being spat at because they were gay or ridiculed . . . that is not a Christian attitude. We have to have the courage to stand up and say that."
He added: "We all belong to one another and there is no way we can build up a society in which people are excluded or insulted.
"We have to learn a new way in Ireland to live with our differences and for all of us to live with respect for one another."
Concerns have been raised that debate could be stifled ahead of the upcoming referendum on gay marriage, after the national broadcaster paid compensation and apologised to officials from the Catholic advocacy group The Iona Institute over comments on homophobia made on 'The Saturday Night Show' by gay rights activist Rory O'Neill, who performs under the drag name Miss Panti Bliss.
Dr Martin called for the debate around marriage equality to be carried out "in a serene and sober way in which people can express themselves and differences can emerge".
Dr Martin also noted: "Just because a person isn't in favour of gay marriage doesn't mean that one is homophobic – let's be very clear on that."
But he added that "all of us have to be careful about the way we speak and the language we use".
On this he highlighted a point he made in his homily at yesterday's Dublin diocesan Mass for the sick at the Church of St Therese in Mount Merrion, during which there was a call for an end to "the clenched fist and the wicked word".
Dr Martin said that at times in society today there was a "harshness and an arrogance and a relentless sense of vindictiveness, both in deeds such as in violence, but also in speech and in public debate".
He urged believers to make their truth known not through harsh words but with the gentle tone of the Gospel.