Mark 14:68

‘But he denied saying, “I neither know nor understand what you are saying”.'

His denial was firm. ‘I do not know what you are saying'. This was a legal form of denial in Rabbinical law. But it would get worse. He was getting in deeper and deeper.

‘And he went out into the porch and the cock crew.'

He immediately moved away from the light of the fire into the shadows of the porch, possibly having in mind that he may have to flee. But it was too late. The maid's interest had been aroused.

‘And the cock crew.' It was cockcrowing (Mark 13:35). Cocks could begin to crow not long after midnight, and then at various times through the night. It seems that Peter distinctly remembered that first signal, as he explained it to Mark. It must have jolted him. But he still did not want to have to leave. Yet he was decidedly uneasy, which was why he made his move.