Neil Lennon's side and are now 11 points clear at the top of the table and remain unbeaten in 18 league outings this season, with the title now surely in their sights.
Commons struck after just three minutes when he collected a pass from Virgil van Dijk before exchanging a well-worked one-two with Georgios Samaras and blasting a shot through the legs of Inverness goalkeeper Dean Brill.
The fourth-placed hosts showed just why they have managed to keep in touch with the leading pack this season, testing Fraser Forster on a number of occasions - most notably through Billy McKay's header and then a powerful drive from Graeme Shinnie.
But Celtic stood firm and held on for a win that keeps them well clear of Motherwell in second place, despite a resounding 5-1 win over Partick Thistle for Stuart McCall's side.
An action-packed first half at Firhill saw the hosts take the lead after eight minutes through Steven Lawless, before goals from Keith Lasley, Zaine Francis-Angol and James McFadden handed the visitors a 3-1 lead at the break, while Lionel Ainsworth and John Sutton added two more midway through the second half.
Elsewhere, Stevie May's hat-trick saw St Johnstone overcome 10-man Dundee United 3-0 at McDiarmid Park, with the visitors having Calum Butcher sent off, while Hibernian recorded a 3-0 victory of their own at home to Kilmarnock.
Paul Hanlon headed home a corner to open the scoring after 12 minutes before Paul Cairney and Lewis Stevenson confirmed the win after the break.
At the bottom, Hearts battled back to claim their first point in five matches with a 1-1 draw away to St Mirren.
Steven Thompson gave the hosts an early lead, before a stunning strike from Jamie Hamill at the start of the second half restored parity.
The result edges Gary Locke's side closer to the zero-point mark after the administration-hit club started the campaign on minus 15.
They moved closer to 11th-placed Ross County, who lost 1-0 to Aberdeen at Pittodrie thanks to an early free-kick from Nicky Low.
