Cahill returns to south London club Millwall's The Den, where his English career began, on Wednesday as Australia take on Ecuador in a World Cup warm-up.
"It's sort of like how the stars have aligned," Cahill told a news conference on Tuesday.
"This is where it all started and to score tomorrow night, if I play, it's just one of those things in your career that would be really special.
"It's a place that I call home along with Everton and to be the all-time leading goalscorer for Australia where it all started might be special, but if it's not here it'll be somewhere else."
Cahill made 217 appearances and scored 52 goals for Millwall during a six-year spell before moving to Premier League Everton for a fee of 1.5 million pounds in 2004.
Now at the New York Red Bulls and about to embark on what would be his third World Cup campaign for the Socceroos, Cahill said he was also looking forward to passing on his knowledge to the new Australian talent coming through the ranks.
"It is a great time for Australia because there is a lot of talent out there and it's started to get unearthed and at the same time kids know they're getting the opportunities," he said.
"I think for me, Mile Jedinak and Luke Wilkshire, it's a great moment in our careers that we can have the responsibility to guide the youngsters and show them the way to do special things for their country."
Crystal Palace midfielder Jedinak has been named as captain for the match with fellow World Cup-bound nation Ecuador.
- Sports & Recreation
- Damian Mori