Tim Farron had initially refused to give a specific right or wrong answer on the subject, saying that all people are sinners and that we should look at our own lives rather than pointing the finger at others.
The Christian leader later resigned on June 14th - just days after polling day - saying he felt "torn" between his faith and his position as a political leader.
On Friday, he told Emma Barnett on 5 Live Daily: "I made the decision about two weeks into the election campaign.
"I thought there isn't a way forward out of this without me either compromising or just causing damage to the party in the long run.
"I kind of thought well, in which case I cannot see a way I will continue to be leader into the future.
"But I kind of thought, right you've got to put that into a drawer, don't talk to anybody else about it, get on and do as good a job as you can during the election."
Liberal Democrat former business secretary Sir Vince Cable has said party leader Tim Farron didn't handle questions around gay rights and his Christian faith well during the election campaign.
The only declared contender for the Lib Dem leadership told Sky's Sophy Ridge On Sunday the leader's position was a "perfectly fair one" but he should have "put these to one side" while enacting public policy".
