The 34-year-old is reportedly not going to have his contract renewed in the summer but the England international showed his true worth to the side again with two strikes in the 2-1 win at Everton.
"Lampard is a great player, a good professional, who is doing well for us and I will try to bring the best out of him until the end of the season," said Benitez. "He is one of the players who if he gets in the box he can be dangerous. He is under contract. He has shown his full commitment. He is a great player and my job is to keep him fit, happy and scoring goals."
A fourth successive league win ensured Chelsea finished 2012 in third place in the table, just four points behind second-placed Manchester City with a match in hand. They became only the third team to win in the league at Goodison Park this year and the first since late March.
"It was a great win for us," added Benitez. "We knew they could be tough but we had confidence in the players. We put Ramires on the right side against Leighton Baines and he gave us a great game too."
Benitez also refused to comment on speculation the club had entered negotiations to sign Newcastle striker Demba Ba.
"We don't talk about our business in public. My job is to prepare for the games, enjoy them if we win and then after they (the club) will let me know what is going to happen," he said. "He is a player who is playing for another team so I don't like to talk about other players."
Everton manager David Moyes was frustrated his side had not taken at least a point from the game having gone ahead so early and then seen Nikica Jelavic hit the woodwork twice before missing an added-time chance to snatch a draw.
"We're not disappointed with the way we've played because we played really well and we've run the European champions really close but we didn't quite have enough in the end," said Moyes.
He added: "We were limited with what we had, not having Phil Neville and Darron Gibson (through injury) and not got Marouane (Fellaini) because of suspension. But Nikica had a great chance to make it 2-2 in what felt like the 94th minute."
Source: PA
Source: PA