The Stay With Me star, who is openly gay and vocal about gay rights, added to his tattoo collection by getting an 'equals' symbol etched onto the third finger of his left hand, as well as three other ink pieces in the same session on Monday (07Dec15).

Sam shared a series of pictures of the new tattoos on and wrote, "First one - the equality sign on my wedding finger. This ones pretty self explanatory. It shows my views on gay marriage and equality for all."

On the ring finger of his right hand, Sam got a rotated version of the 'equals' symbol, which appears like the Roman numerals 'II', and he explained in the caption, "This tattoo is inspired by one of the oldest tattoos ever found on a mummified body that was found buried alone in the ice."

The pop star is also sporting tattoos of the words "honesty" and "alone" on the upper section of each arm. Showing off the 'honesty' ink, Sam added, "This is what I promise to be in my music. It's what I live by. In the words of (singer Maria Mena) 'Honesty is my God'", and of his 'alone' addition, he wrote, "And lastly - this is just me being a melancholy t**t haha (sic). I do see it as a small positive thou (sic)... No longer lonely... Just alone... Which is ok... thought I'd share these with you because I love them."

Sam has already got tattoos of the Roman Numeral 'III' on his inner wrist, which his sisters also have, an anchor on his arm to thank his supporters, and an ice cream cone on his left leg.

He has previously described why he got an airplane etched on his right leg, telling, "(I was) drunk in Malia at 18 and I'd just got off the plane, so I got a plane."