The midfielder strode on to Andy Barcham's lay back and smashed the ball into the top corner with his right foot from 25 yards in the 57th minute at Broadhall Way.
It was a goal worthy of winning any game and made sure the Barclays Reserve League South champions finished their home campaign with another victory - their 15th in the last 17 games.
Clive Allen's men will now complete their league programme at Coventry on April 25 before an end-of-season play-off against the Northern champions - likely to be Manchester United or Aston Villa, on a date yet to be decided.
Development coach Clive made it clear before this penultimate league game that he wanted to finish in style with victories over the Sky Blues.
He drafted Leigh Mills and Stuart Lewis back into the starting line-up with Tommy Forecast in goal while Hossam Ghaly and Tom Huddlestone took the central roles in midfield with Jackson left and Dean Marney on the right.
The game started at quite a pace with chances at either end - Lee Barnard and Marney went closest for us - but a lull in the goalmouth action followed as the sides cancelled each other out and the first half ended goalless.
Competitive Coventry managed to get into a few promising positions but were presented their best chance on 53 minutes when Forecast's hurried clearance went straight to Hildreth on the edge of the box - his lob cleared the stranded keeper and the crossbar.
However, Jackson's wonderful strike signalled a dominant final half-hour and although the visitors threatened on occasions - most notably Louragnon's late chance - a second goal always looked the more likely.
Ghaly, Marney and Mills all had opportunites before Tuffey produced the save of the night to tip aside Barnard's volley. The top scorer also headed onto the roof of the net, Ghaly fizzed another shot wide and Andy Barcham hit the crossbar in injury time. Another job well done.
1min: Huddlestone control and laid wide to Barnard, he cut inside Giddings before curling just wide with left foot from 20 yards.
2mins: Marney lashed over from 30 yards.
4mins: CLOSE. Hildreth deep cross found Lynch at far post, he skidded side-foot inches wide.
9mins: Well-crafted move involving Mills, Lewis, Barcham, Ghaly and Huddlestone ended with Marney on the end of Ghaly's dinked pass, instant volley just wide.
12mins: Thornton's volley from Hildreth's corner looked goalbound until Bunjevcevic threw himself in to block.
19mins: SUB. Spurs - McKie on for injured Martin.
35mins: McCrink fed ball through to Reid, Forecast out to meet him and Reid went over challenge, Coventry appeals ignored.
36mins: Marney picked out Jackson in space right side of box, elected to cross and ball cleared.
39mins: Wall miscontrolled Jackson's cross from left, Barnard onto it in a flash but volleyed over from 12 yards.
Added time: Jackson fine pass picked out Marney's run inside, controlled well but got underneath shot from 25 yards.
Half-time: Spurs 0, Coventry City 0
53mins: Bit of a defensive calamity as Forecast lost control of Mills' wayward backpass, ball fell to Hildreth on the edge of the box, open goal but lobbed over Forecast and the crossbar.
57mins: GOAL. Fantastic strike from Jackson. Barnard brought down a long clearance, Barcham laid it back and Jackson hit a thunderbolt with his right foot into the top corner from 25 yards. 1-0.
62mins: Jackson important touch away as Davis turned Hildreth's corner towards goal.
63mins: Lewis sent Marney clear down the right, he cut back for Ghaly to slide over from 10 yards.
68mins: Mills in to make fine tackle as Reid prepared to pull the trigger from 12 yards.
71mins: Marney side-footed across goal and just wide.
72mins: Reid burst into box, cut onto left foot, drove into side-netting.
76mins: Mills dived in to meet Jackson's corner at the near post, looked goal bound until it clipped off Davis and just wide.
76mins: SAVE. Tuffey at full stretch to tip aside Marney's sweet volley from 22 yards.
79mins: Barnard flicked Jackson's corner onto the roof of the net.
84mins: CHANCE. Ogarro played one-two with Reid and was clear down the left, cross found its way to Lorougnon at far post, had time to pick spot but didn't get hold of it and Forecast saved.
85mins: Ghaly drove wide from 30 yards.
89mins: WOODWORK. Barcham headed Ghaly's free-kick against the crossbar from six yards.
Full-time: Spurs 1, Coventry City 0
Line-ups: Spurs: Forecast, Lewis (Davis, 77), Martin (McKie, 19), Ghaly, Mills, Bunjevcevic, Marney, Huddlestone, Barnard, Barcham, Jackson. Subs: Burch, Maghoma, Hamed.
Coventry City: Tuffey, Jones, Giddings (Davis, 46), Wall, Bains, Hildreth (Loroughnon, 70), Ogarro, Thornton, Reid, McCrink (Burtoft, 70), Lynch. Subs: Belford.
Johnnie Jackson struck a goal worthy of the occasion as our reserves celebrated picking up the championship trophy with a win against Coventry on Monday night.