It's the first time the Patriots have ever advanced to the Play Offs in the CPL's four year history.
Lewis was the early aggressor, hitting 5 fours and 6 sixes as he blazed his way to 69,
But then Gayle opened up his shoulders gradually as he raised his 50 off a relatively sedate 46 balls, before unleashing a late blitz to reach 71.
The Patriots posted a massive 208 - the highest score in the competition this year.
It proved a mountain too high for Gayle's former franchise, the Jamaica Tallawahs, who could only muster 171 in response.
Tevon Griffith tried his best, hitting 42 at the top of the innings as they attempted the huge chase but his effort, and late salvo from Rovman Powell weren't enough as they were pegged back regularly by the Patriots bowlers, lead by Mohammed Shamsi's three wickets.