Thomas joined Emmerdale as Adam Barton in 2009, forming part of the soap’s new Barton family. Thornton played the patriarch of the clan, John, before quitting last year.
Thomas told Inside Soap that he still keeps in touch with Thornton describing him an “absolute gem”.
“I miss everything about working with him. That guy had such a big impact on my life, both in and out of the studio.
“James is an absolute gem and if I grow up to be half the man he is, then I’ll be a happy guy.
“I don’t get to see him as much as I’d like to because he lives in London, but we catch up on the phone whenever we can and he gives me fatherly advice.”
Thomas also praised Danny Miller who played Adam’s best friend Aaron Livesy in the soap, before also bowing out last year.
“I loved working with Danny. All the stuff surrounding Aaron’s coming out has a special place in my heart. Getting to work with one of your best mates is a great experience. I see Danny a lot – we play golf together.”
Adam [Barton] is currently embroiled in a marital spat between Katie Macey (Sammy Winward) and husband Declan (Jason Merrells) after Katie seduced him to wind up Declan.
Emmerdale continues tonight at 7pm on ITV1.