Which sentence is correct? He thought about getting up but decided to lie there a while longer. OR He thought about getting up but decided to lay there a while longer. I think it's lay because the sentence is past tense. Help?

I think is lie but still not sure.
(Present)Lie- lay(past)
(Present)Lay-laid(past)

It's a great question.

It's "to lie there..."

Here's the lesson on lay and lie.