The phrase law of the land is a legal term, equivalent to the Latin lex terrae (or legem terrae in the accusative case). It refers to all of the laws in force within a country or region, including both statute law and common law.
In the year 1297 this term was used in the Magna Carta. Perhaps the most famous clause of Magna Carta states:
No Freeman shall be taken or imprisoned, or be disseised of his Freehold, or Liberties, or free Customs, or be outlawed, or exiled, or any other wise destroyed; nor will We not pass upon him, nor condemn him, but by lawful judgment of his Peers, or by the Law of the Land.
This is sometimes called the "law of the land clause".
Half a millennium later, following the American Revolution, legislators looked to Magna Carta for inspiration, and emulated some of Magna Carta's language. Versions of it can be found in the Virginia Constitution of 1776, the North Carolina Constitution of 1776, the Delaware Constitution of 1776, the Maryland Constitution of 1776, the New York Constitution of 1777, the South Carolina Constitution of 1778, the Massachusetts Constitution of 1780, and the New Hampshire Constitution of 1784.
Some people are always Heaven made
Some people will live impermanent for the rest of their days
Time marches on
Yesterday is better than tomorrow
Life is uncertain, let me hear you say, "Yeah"
That is that, oh yes, it is
There'll be days of sunshine and laughter
But don't forget you will have to shed some tears, oh
It's the law of the land, my brother, oh
Whether you like it or you'll understand, ah hey hey
It's the law of the land, hey hey, hey hey
'Cause made by almighty men
Live by the good book if you're able
You must play your cards on top of the table
When you gather, you either win or lose
In life's everybody's got to pay some dues, well
It's the law of the land, well well well
Whether you'll like it or you'll understand, you can't change it
It's the law of the land, ah how
'Cause made by almighty men, oh hey
Hey, it's the law, the law of the land
Whether you'll like it or you'll understand
It's the law, the law of the land
'Cause made by almighty men
A teacher man can't be found
Until you find yourself, think about it
You might not like being, well you ought, but you'd better start like it
But you sure can't be nobody else
In other words, I can't be you, ain't no quit, yeah
You can't be me, well well
That's all with you, my sister and brother
And that's the way that good life meant to be, hey ho
It's the law of the land, well
Whether you like it or you'll understand, say say
It's the law of the land, hey yeah oh
'Cause made by almighty men
Look at here
The tools of a man's day has got him by corrupt
For your own protection your Gods you must love
What goes around, comes around
And what goes up, yeah, must come down, aha
It's the law of the land, well well well well
Whether you like it or you'll understand
It's the law of the land, well well well
'Cause made by almighty men, aha
It's the law of the land, everybody else say