Rap star Macklemore has spoken out in a rare interview about his reasons for writing a song with a strong pro-equal marriage message, saying he wants to “challenge society” and issues that others “are afraid to address”.

The song Same Love, from his latest album collaboration with Ryan Lewis, addresses the straight rapper’s personal experiences and feelings around the issue of same-sex relationships and equal marriage, and features a video spanning the lives of a gay couple, including a happy marriage.

Speaking about the issues tackled by the song, Macklemore said in the interview with the New Review in the Independent on Sunday that he wanted to go for issues other people “are afraid to address.”

He based the song on his gay uncles, and godfather, and said he was anxious when it came to playing the song for them for the first time. He said: “I was really nervous to play it for them.

“It’s obviously a very personal song, and I didn’t want to cross any boundaries in terms of their privacy. But we actually ended up taking a picture of them and using it as the cover art for the single.

“I wanted the art to reflect how personal the song was, and they are a big reason why I’m so passionate about the issue.”

He went on to say that he wanted to “challenge society”, through his music with issues such as equal marriage, citing honesty and openness as important elements in his music.

“I wanna challenge myself, I wanna challenge society, and I wanna be the best version of myself, and the way I can do that is by expressing and talking about concepts that no-one else will, that people are afraid to address.

“I wanna be able to talk about those openly and honestly and figure myself out and help those who listen to the records figure them out.”

Same love topped the Australian singles chart earlier in 2013, and has reached number 82 of the US Hot 100.

Macklemore rose to fame last year with his song Thrift Shop, which reached number one in the UK chart. Follow up Can’t Hold Us, is also gaining momentum worldwide.

The full interview with Macklemore will be in this weekend’s The Independent on Sunday on 19 May, and the video for Same Love is available to view below.