Following a departure from Shakhtar Donetsk in 2018, Bernard secured a move to Everton and amassed for himself 73 Premier League games for the Toffees.
Bernard thanked the fans of his former side after putting pen to paper.
"Since I arrived [at Everton] I was always well received and treated as if I was really a member of the family.
"Unfortunately you who support me, and not those who appear here to spread the words of hate, don't know half of what happens behind the scenes. I wanted to be more clear but unfortunately today I can't.
"The message I leave today is of gratitude and you will always be special. Everton is giant, has an incredible history and has the structure and capability to return to be and to conquer everything that it has been and conquered.
"I'm satisfied about how much I dedicated myself and did my best to be the best of me in all training and games."
Bernard nearly moved to Middle East after Saudi Arabia-based club Al-Hilal tendered in an official offer to Everton last year.
The Brazilian winger was in the last part of his contract with Everton and with the club knowing they could lose him on a free agent next year have rather cashed-in on the 28-year-old.
Everton will be led by new manager Rafael Benitez, replacing Carlo Ancelotti, who departed the side to Real Madrid.
Bernard having been restricted to just three Premier League starts under Ancelotti managed to featured 12 times for Everton in the Premier League last season after returning from a long injury.
Everton have also brought in new additions in the shape of Andros Townsend, Demarai Gray and Asmir Begovic to help a side that finished 10th last term earn European football spot this time around.
