The Statute of Marlborough - 1267

The Statute of Marlborough is one of the oldest law in England that has not been repealed, it dates from 1267. 

Why was it passed, what was it's purpose and  what parts of it are still in force?

In the Year of Grace, One thousand two hundred sixty-seven, the two-and-fiftieth Year of the Reign of King Henry, Son of King John, in the Utas of Saint Martin, the said King our Lord providing for the better Estate of his Realm of England, and for the more speedy Ministration of Justice, as belongeth to the Office of a King, the more discreet Men of the Realm being called together, as well of the higher as of the lower Estate:  It was Provided, agreed, and ordained, that whereas the Realm of England of late had been disquieted with manifold Troubles and Dissensions; for Reformation whereof Statutes and Laws be right necessary, whereby the Peace and Tranquillity of the People must be observed; wherein the King, intending to devise convenient Remedy, hath made these Acts, Ordinances, and Statutes underwritten, which he willeth to be observed for ever firmly and inviolably of all his Subjects, as well high as low.

• Statute of Marlborough 1267 [Waste]  

• The Statute of Marlborough 1267 [Distress] 

I would like to credit Purple Planet Music - Future Worlds for the introduction and exit music - Link.