Our love was born afraid
A simple sailor to betray
Love was vulnerable
Scared of heights, sure to fall
Equals's official lyric explanation
So, basically, this song it’s obviously a love song and it’s about how when you start off in a relationship it’s quite vulnerable. So, you don’t know if it’s going to work out, the “simple sailor to betray” is like saying that it’s, kind of, almost foetal - so it’s very young, naïve and, therefore, easy to betray.
Then the second part of the chorus switches the tense, so it says “our love was…” and then now it says “our love is a single soul…” So, it’s about that relationship blossoming and becoming one solid loving unit, I guess, that’s harder to betray and break down.