KJV Deuteronomy 1 : 3
And it came to pass in the fortieth year, in the eleventh month, on the first day of the month, that Moses spake unto the children of Israel, according unto all that the LORD had given him in commandment unto them;
In the above text it is just stated that it was the fortieth year when Moses addressed the children of Israel between Paran and Tophel.
But there is no mention from which event this fortieth year is reckoned
Fortieth year from which event?