The Hoops faced off against Young Boys in the Champions League and could have been four goals up had it not been for offsides and a missed penalty.
Idah came off the bench in the second half and finally broke the deadlock when his effort deflected off Young Boys captain Loris Benito for an own goal.
Celtic held on for a crucial win, which means they will reach the knockout stages of the Champions League for the first time in years, thanks to the revamped playoff structure.
Idah, the hero of the night, described the feeling of qualifying as "indescribable."
"This feeling is indescribable. This is where we wanted to get to. We've been great all season and all through this campaign, and now there is still time to push on," he told TNT Sports after the game.
⚽ Celtic 1-0 Young Boys
"It's amazing... We'll go as far as we can" - Ireland forward Adam Idah revelled in Celtic securing a knock-out place, thanks to his game-changing impact off the bench
📺 Reaction on @RTE2 and @RTEPlayer#ChampionsLeague pic.twitter.com/2pQ7uRvSjc— RTÉ Sport (@RTEsport) January 22, 2025
"It was quite frustrating, but to be fair to the boys, they were brilliant. There are not many games where that happens, and I think the boys were quite confident going into the second half."
Idah was also asked about the influence of Celtic boss Brendan Rodgers and said the manager told him to simply be himself.
"Anytime I come on, he says, ‘Do your thing and be yourself.’ These are the games I want to play in and have an impact in, and to be fair to the gaffer, he's unbelievable. He lets me be myself."
Although UEFA's website will list Idah's strike as an own goal due to footballing rules, the forward, who had been on a barren spell of late, admitted that he doesn't mind. In his eyes, he is the rightful goal scorer.
"I got a bit lucky, but we'll take it. I said to the boys, ‘I don't care; that's my goal.’
"I think we can go far. We've got a great squad; we've come this far, so why not dream big? We'll go as far as we can."
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