Lyric Problems: Belinda Carlisle's "Heaven is a Place on Earth"

Belinda Carlisle claims again and again in her 1987 Billboard #1 hit "Heaven Is a Place on Earth" that:

"They say in heaven, love comes first."

No, they don't. This is not a commonly used (or ever used) expression. No one says this. This song is the only place where these words are spoken.

In fact, I ran a search on the King James Bible. The three words "love comes first" do not appear sequentially anywhere in The Bible.

Also, who are "they?"

Donald Trump is fond of say that "People are saying this..." and "They say that..." but he's lying every single time. Absent of an actual, quotable human being, Trump claims that people are speaking in his favor but is incapable of pointing to any specific person. 

I'm not attempting to compare Belinda Carlisle to Donald Trump, and I understand that there's a big difference between the veracity of the President of the United States and a musician. Carlisle didn't even write the song. That credit goes to Rick Nowels and Ellen Shipley.

Still, "they" don't say in heaven that "Love comes first." Not as far as I can tell.  

That lyric has annoyed me for 30 years.