Cat Stevens "I love my dog"?

Can anyone fill me in on what Cat is trying to say in the song- “I love my dog more than I love you” -

Is it a joke, insult, term of endearment or should we be sending the RSPCA around to Cats home asap to check his sleeping arrangements? If I said that to my wife my survival chance would be very slim indeed. I does seem a very odd song indeed.

He was 18 or 19 when the song was published, but he might have wrote it much earlier.

I would chalk it up to a youth being ingenuous.