Jesus impressed without getting on the scoresheet in his competitive Gunners debut against Crystal Palace, but the former Manchester City striker delivered the goods on Sunday (AEST) to make up for some questionable Arsenal defending.
The Brazil international's double put Arsenal into a commanding first-half lead, and he capped off a brilliant display with two second-half assists after Arsenal twice gifted Leicester some hope.
Granit Xhaka netted Arsenal's third after William Saliba's own goal, and after James Maddison struck through Aaron Ramsdale's legs to make it 3-2, Jesus set up Gabriel Martinelli to complete the scoring.
The post came to Leicester's rescue in the 20th minute when Xhaka headed against the upright, but its good fortune ran out when Jesus’s deflected effort curled in over Danny Ward.
It was 2-0 in the 35th minute, Jesus doubling his tally by nodding in unmarked from a corner.
With Jesus having twice come close to a third, Leicester thought it had a lifeline when Jamie Vardy went down under pressure from Ramsdale, yet referee Darren England overturned his decision to award a spot-kick after a video assistant referee (VAR) check showed there was little contact.
Saliba's blunder – an inadvertent header beyond Ramsdale – gave Leicester a route back into the match, but the Foxes conceded again just 106 seconds later.
Ward spilled what should have been a simple catch, and Xhaka was on hand to sweep home from Jesus's lay-off.
Maddison's crisp shot and poor goalkeeping from Ramsdale dragged Leicester back into it with 16 minutes remaining, yet Arsenal hit back swiftly again – Martinelli drilling in from the edge of the box.
Jesus struck the post with the goal gaping as a hat-trick chance went begging, but his key contribution on his home Premier League debut for the Gunners sealed all three points.