John Gill Commentary Luke 22:55

"And when they had kindled a fire in the midst of the court, and had sat down together, Peter sat in the midst of them." — Luke 22:55 (ASV)

And when they had kindled a fire in the midst of the hall ,
&c.] It being cold in the night time, though it was at the passover, and the beginning of harvest, the servants and officers of the high priest made a fire in the middle of the hall, whilst Jesus was examining before the sanhedrim, at the other end of it: and were sat down together ;
about it, as the Syriac version adds, to warm themselves: Peter sat down among them ;
for the same purpose, and as if he was one of them; and which he might do, not only to warm himself, but to prevent his being taken notice of, and suspected; as he might have been, had he been loitering about.