Brendan Rodgers' men have lost just once in their last 12 league games and Tielemans believes another gritty win proves their top-four staying power.
“They (Villa) are up there with us and it was a massive win to show that we're still up there," he said.
“I think it was a really good first half, especially. In the second half, where they scored early on, we had to stay compact, stay very narrow and dig in until the end and to keep the score.
“That shows our mentality, our composure as well under pressure.
“The first half was really good. We scored two really good goals and then we tried to keep the ball and manage the game."
Leicester next host Slavia Prague in the second leg of their Europa League last-32 tie on Thursday, having drawn 0-0 draw in the Czech Republic last week.
But Maddison is now a doubt after coming off in the second half at Villa Park with a hip injury.
“I think European competition is always very nice to play (in)," Tielemans told LCFC TV.
“You always play very different types of teams, which is very enjoyable and hopefully we can finish the job on Thursday. It is going to be a very tough game but I hope the guys will be fired up for it."