The French striker has scored 13 goals in the Premiership this season with eight coming in the last four matches including a double against West Brom on Saturday.
"We soaked up a lot of pressure from West Brom early on and hit them on the counter-attack with three great goals. Anelka has been on fire and some of his link-up play, as well as his goals, has been brilliant,” Terry said.
"He has been, and is, the saviour for us at the moment with Didier having been out and only just coming back after injury.
"For me, Anelka is in the best form of his career. When we signed him I said 'Thank God you are here' because I used to hate playing against him.
"He was always a problem, always playing on my shoulder, and a great finisher as well. He is in great form and getting the goals as well. He is top scorer in the Premier League and long may it continue.
"He relishes playing down the middle. He relishes the likes of Flo (Florent Malouda) and Coley (Joe Cole) and Solomon Kalou on either side of him.
"It gives him the chance to play in between the two centre-halves and on the shoulders of them because the two opposition full-backs are getting stretched all the time by the wide men."