Shelvey scored Swansea's opener and created their second but his two shocking passes set up both goals for Liverpool who moved a point clear of Arsenal and Tottenham Hotspur at the top of the table.
"I thought for the first 65 minutes we were very, very good with and without the ball. We had to show character after going behind so early," Liverpool manager Brendan Rodgers told Sky Sports after the match against his former club.
"This will be a really big point for us."
Shelvey, who joined Swansea for 5 million pounds from Liverpool in July, gave his new team the lead after two minutes when he swept a shot into the net at the second attempt from six metres.
But two minutes later his weak back pass was pounced on by Daniel Sturridge who fired the ball past goalkeeper Michel Vorm for his fourth goal in four games this season.
Another loose pass by Shelvey after 36 minutes was easily picked off by Victor Moses and the winger, on-loan from Chelsea, broke forward and slotted the ball past Vorm from the edge of the area.
Shelvey's deft header set up striker Michu for Swansea's equaliser after 64 minutes and the home side, 13th in the standings with four points from four games, looked more likely to snatch a winner in the closing stages.
"The way we came back in the second half was excellent. It was a really difficult first half, after having the best start of all," Swansea manager Michael Laudrup said.
"The goals came from huge mistakes. But that is part of the game.
"We got the equaliser, and in the end it was a very good point for us on a night which could have gone wrong for us with some of the things we did wrong in the first half."
Image: Swansea City's Jonjo Shelvey (left) gets past Liverpool's Mamadou Sakho before scoring during their English Premier League match at the Liberty Stadium, Swansea, Wales.
Photograph: Rebecca Naden/Reuters
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