The Hoops returned from the winter break which included a training camp in Spain to hit the ground running with two convincing wins at Parkhead.
A 4-1 thrashing of Hearts was followed by a 4-0 thumping of Dundee United, results and performances which cemented their place at the top of the Clydesdale Bank Premier League and buoyed the Celtic boss ahead of the trip to the national stadium where they have the chance to reach the first cup final of the season.
"I am delighted, they have played great," said Lennon.
"Playing at home this season, at times, was a bit of a bugbear but they seem to have found their mojo at home and the last two performances have been superb.
"One of the criticisms I had of the team, particularly in domestic games, was that back to front we were excellent in our build-up (but couldn't score).
"We had about 70 per cent possession against Hibs and couldn't score but now we have found our goalscoring touch in the last two games and that is really pleasing.
"I have no idea (why), maybe they just needed a break.
"But I looked at the schedule coming up and it is really heavy, there is no respite for the players."
The in-form Parkhead men are overwhelming favourites to beat a struggling St Mirren team who have not won a point nor even scored a goal against Celtic in their last eight meetings.