The Catalans lost their opening game at Numancia at the end of August and drew their second against Racing Santander at the Nou Camp, but then went on a nine-match winning run and have amassed 28 points, three more than unbeaten Villarreal in second.
"We are playing at a very high level," Messi said on the club's website ahead of Sunday's home tie against mid-table Getafe.
"But the most important thing is what happens at the end and we have to try to maintain this level through to the last day of the season," he added.
"We have to carry on playing the same way, continue to develop and collect points so that both we and the fans can enjoy ourselves."
Barca were able to extend their lead last weekend when none of their rivals in the top four won.
Villarreal conceded a late equaliser to draw 2-2 at Malaga, third-placed Valencia lost 3-2 at home to Sporting Gijon and Real Madrid's poor spell of form continued with a 1-0 defeat at Real Valladolid to leave them in fourth.
PUBLIC BACKING
Injury-plagued Real have had the added distraction this week of having to give public backing to beleaguered coach Bernd Schuster amid speculation his days at the Bernabeu are numbered.
But there was also some good news when central defender Pepe and midfielder Mahamadou Diarra both recovered sufficiently from recent knocks to go on midweek international duty for their respective countries, Portugal and Mali.
Villarreal could be boosted by the return of Nihat Kahveci for Saturday's game against Real Valladolid after he grabbed a couple of goals in a training match on Wednesday, the club said on their website.
The Turkish striker, who has been out with a leg injury, was the club's top scorer last season and his goals played a key part in Turkey's progress to the semi-finals of the European Championship in Switzerland and Austria in the summer.
Valencia striker Fernando Morientes said the club are in good shape ahead of Saturday's clash at fifth-placed Sevilla despite last week's setback.
"There is not much we need to change and we need to get back to the positive dynamic we had at the start of the season," he said on the club's website.
"We are fairly reliable away from home and let's see if against a team like Sevilla, which likes to play the ball around, we can create opportunities and get the three points."
