Unbeaten Celtic equal 50-year-old 'Lisbon Lions' record
Dedryck Boyata's 72nd minute strike at Celtic Park ensured Brendan Rodgers' side stretched their unblemished start in all domestic campaigns this term.
The Glasgow team's unbeaten streak draws them level with the run achieved in the most successful season in Celtic's history -- the 'Lisbon Lions' 1966-67 campaign, which ended with a clean sweep of trophies including the European Cup.
The win -- Celtic's 16th consecutive victory in the league -- also sees the runaway league leaders extend their advantage to 22 points over rivals Rangers in second place.
"To be 22 points ahead at this stage of the season, I'm very happy. The overall performance was very good," said Rodgers.
"Tonight, we should tip our hat to the players because they've been absolutely brilliant."
St Johnstone manager Tommy Wright said defeat was a bitter blow.
"I think my side couldn't really have done much more tonight," he said. "Unfortunately we couldn't get a goal as I think they deserved something from the game for all the effort and commitment they put in."
Neither side showed any signs of rustiness as they returned to league action for the first time in 2017 following a three-week winter break and both had early chances to open the scoring early on.
Scott Sinclair thought he had given Celtic a 10th minute lead when he headed James Forrest's cross past Zander Clark but his celebrations were cut short by the assistant referee's flag who adjudged that the ball had gone out of play in the build-up.
Celtic captain Scott Brown, making his 400th appearance for the club, then set up Kieran Tierney for a chance but he blazed his effort over.
St Johnstone were unfazed and Steven Anderson came close for the visitors when his hooked shot was tipped over by Craig Gordon as play spread from one end to the other.
Zander Clark made a fingertip save to keep out a fizzing strike from Stuart Armstrong and from the resultant corner Boyata saw his header knocked off the line by Saints defender David Wotherspoon.
Moments later, Danny Swanson saw his volley crack off the base of the post as Celtic failed to clear their lines from a corner.
As the half drew to a close, Celtic laid siege to the St Johnstone goal with Moussa Dembele twice firing narrowly wide before Clark was forced to turn a Forrest strike round the post at full-stretch.
Celtic dominated possession at the start of the second half as they kept St Johnstone pinned down in their own half but failed to really test 'keeper Clark.
Forrest sent a shot well over and Clark easily held a long-range effort from Brown as the visitors soaked up the pressure.
Patrick Roberts replaced Forrest on the hour mark and the on-loan Manchester City winger almost made an immediate impact as he burst into the box and cut the ball back from the by-line for Sinclair who somehow prodded his shot wide from close range.
The breakthrough finally came following a period of intense pressure.
Boyata saw a goal-ward bound header frantically turned round the post by Clark but the Belgian wasn't to be denied from the resultant corner from Armstrong as he rose above his marker to bullet a header into the net.