The song is called "The Blessing" and it's by a Scottish band called "Electrics". Apparently it's an old Irish Blessing or prayer or something. You're British aren't you? I'm an American. You're the one who should know this. Lol! Just kidding. I heard it only ONE TIME, several years ago, loved it instantly and had it stuck in my head for years (after only hearing it once), but I could only remember one line. I finally found it just today, but before finding it I happened upon your question, and once I'd found the song, I signed up for an account so I could get you this info. I found a copy of them playing it live on Youtube, but couldn't find the album version. Here's the one I found, though:
https://www.youtube.com/watch?v=HhBOwTnmgCY