Spurs ended a game with 10 men for the second time in a row after Kaboul saw red for a second-half clash with Newcastle midfielder Cheik Tiote. After being tackled perfectly legally by Tiote, Kaboul squared up head to head with his opponent and referee Anthony Taylor deemed the offence worthy of a straight red card.
"We shouldn't have gone down to 10. It was stupid," said Redknapp after Aaron Lennon and Gareth Bale scored either side of Kaboul's moment of madness to send Tottenham into the Champions League places.
"It's a lack of discipline. He has got to learn. You are 1-0 up so why do you have to get involved in something like that? It's absolute nonsense and he has to learn.
"He is a young boy and has been fantastic for us this year. He has been everything I always thought he would be. Now he has become a top-class centre-half but he has gone and got himself suspended for three games."
Tottenham take on Fulham on New Year's Day and Redknapp wants to end the festive season unbeaten having taken the scalp of Aston Villa with a 2-1 win on Boxing Day.
"It has been a great run in the Christmas period," he added. "It puts us in a great position. We have got six points so far and if we can get three more on Saturday it will be fantastic for us."
Newcastle manager Alan Pardew hailed the performances of Bale and Lennon, who were Spurs' biggest threat throughout.
"Their pace down the flanks was probably the difference between the two sides," he said.
"The pace they have can undo you and your discipline as a back four and you want that in your team, you want that directness."
Source: PA
Source: PA