Somehow I had never heard this song, or even heard of it, though I am familiar with the great Leon Russell. Seems at least partly inspired by the book:

How many days has it been
Since I was born?
How many days
'Til I die?

Do I know any ways?
That I can make you laugh
Or do I only know how
To make you cry?

When the baby looks around him
It's such a sight to see
He shares a simple secret
With the wise man

He's a stranger
In a strange land
Just a stranger
In a strange land
Tell me why?

He's a stranger
In a strange land
Just a stranger
In a strange land

How many miles will it take
To see the sun?
And how many years
'Til it's done?

Kiss my confusion
Away in the night
Lay by side
When the morning comes

And the baby looks around him
And shares his bed of hay
With the burrow
In the palace of the king

He's a stranger
In a strange land
Tell me why?

He's a stranger
In a strange land
Just a stranger
In a strange land
Just a stranger
In a strange land

Well, I don't exactly know
What's going on in the world today
Don't know what there is to say
About the way the people are treating
Each other, not like brothers

Leaders take us far
Away from ecology
With mythology
And astrology

Has got some words to say
About the way we live today
Why can't we learn
To love each other

It's time to turn a new face
To the whole world
Wide human race

Stop the money chase
Lay back, relax
Get back on the human track
Stop racing toward oblivion

Oh, such a sad
Sad state we're in
And that's a thing

Do you recognize the bells of truth
When you hear them ring?
Won't you stop and listen
To the children sing?
Won't you come on and sing it children?

Stranger in a strange land
Stranger in a strange land
Stranger in a strange land
Stranger in a strange land
Stranger in a strange land

I don't read any specific Heinlein influence there; it's a '70s ecology ballad based on the biblical phrase. IMVHO.

I know Leon and his family I will try to ask him when he recovers from his surgery.

Thank you for that--I'd be interested if he's read the book.