Tony McMahon's goal midway through the second period at the Proact Stadium helped the Bantams to victory in their first league game in December.
Following the postponed Southend United match the weekend before, the Chesterfield game was City's first in two weeks and their first league fixture since the trip to Walsall at the end of November.
Despite the recent lack of action on the pitch before the Chesterfield win though, Parkinson says his players have been showing no signs of ring rust - far from it in fact.
The City chief reckons there in a growing spirit and belief within the camp at present and he hopes that can continue going into the traditional festive fixtures.
Parkinson said: "The lads had their Christmas do last weekend (after the postponed Southend United fixture). When they came back into the club the following Tuesday, I have to say it was probably one of the best training sessions that I can remember.
"There was a real edge about the lads. You could almost sense by the way they trained that they had enjoyed their break and they were ready to go again.
"That is credit to the group. They almost manage themselves really in the way they drive each other on in training and when they stay out after training to work on things.
"That is the environment we need about the place to keep improving as individuals and to help the team.
"Once again on Saturday, we had key players not quite making it into the starting eleven.
"It is always a difficult call to make for myself and the staff. What is pleasing to see though, the boys who don't get picked are still staying right behind the team and wishing the lads all the best for the game.
"That is just as important as players putting their energy into a game out on the pitch.
"There is a real togetherness about the boys and we have to keep it there.
"The work ethic within the team is the most important thing for me, and I think everyone at the game on Saturday could see the hard work the lads were putting in."