The Czech Republic international joined the Gunners after falling down the pecking order at Stamford Bridge behind Thibaut Courtois.
Cech has been a regular fixture in the Arsenal first team since his arrival at the club and has played every minute of the Gunners’ Premier League campaign so far this season.
The 33-year-old kept a clean sheet as Arsenal were held to a goalless draw at Stoke City on Sunday to reclaim their place at the top of the Premier League table.
And Walcott feels that Cech’s arrival has helped to spread a new-found confidence throughout Arsene Wenger’s side.
Walcott told Arsenal’s website: “The mental strength in our dressing room is the strongest it has ever been.
“When you have the likes of Petr Cech coming in as well, he only enhances that.
“He has lifted everybody’s heads up, saying this is a very good point and that nobody tends to win here.
“We just have to look at him because he has been at the top level and won many things so if we have the belief that he has got, we can push on.”
Arsenal are top of the Premier League on goal difference from Leicester City as they head into next Sunday’s crunch clash with Chelsea at The Emirates.
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