Redknapp, who managed Spurs from 2008 to 2012 and led the club into the Champions League for the first time in the modern era, wrote in The Sun: "With belief, anything is possible. And injecting Tottenham's players with much-needed confidence will be the biggest task for interim boss Igor Tudor when he walks through the doors to meet his squad."
He added: "The message for Tudor now is similar to the one that I used when I arrived at White Hart Lane in 2008. We had fantastic players whose confidence was on the floor having not won any of their first eight league games.
"So the first thing I did was to lift the spirits of Luka Modric and Gareth Bale and remind them just how good they were, the quality they had and what they could do to the opposition. I had to make Modric truly believe there was no one better than him in the Premier League at that time. And everything flowed from belief.
"The players cannot be embarrassed to work, run after every ball and, when you lose it, keep chasing and pushing."
Redknapp also suggested that young stars Lucas Bergvall and Archie Gray, the latter hailed as a 'future Tottenham captain', could be the players to help propel the team away from the drop zone, while he also dismissed suggestions that Cristian Romero should be stripped of the armband.
"There are still a few players Tudor will need to deal with and none more so than the captain Cristian Romero," Redknapp continued.
"You cannot take the armband away from him, as much as that would seem an easy fix. Strip Romero of the captaincy and then you have lost him from day one.
"For the short term, you need him on your side and with you - but there needs to be a frank conversation about his lack of discipline."
He added: "A fine example for Romero and the rest of the squad to follow is 19-year-old midfielder Archie Gray. He was Tottenham's player of the year for me last season and delivers whenever or wherever you play him.
"Gray is a future Tottenham captain and everyone should be looking to him. He puts on a performance and shows commitment and desire whether at right-back, centre-back or in midfield.
"The kids at Tottenham, both Gray and Lucas Bergvall, have been showing up the leaders for far too long and it is time the more senior figures followed their lead."