When Peter denied the Lord and cursed, was he saved? He had already declared Jesus the Messiah so I would assume he was. Did he have the Holy Ghost? After the resurrection, he was strong in his faith even unto death. What made him stronger than before?
Some scholars say that when we fall it’s more likely to be in an area of our strength rather than a weakness. This was certainly true of Peter. Several times he made some bold statements about his faithfulness. He boasted that even if everyone else deserted the Lord he never would (Matt. 26:33), and he stood with a drawn sword against the entire contingent of soldiers sent to arrest Jesus (John 18:10).
But at a critical moment, he was confronted by a powerless servant girl and denied even knowing Jesus. Because of his immediate remorse (Matt. 26:75), I don’t believe he ever lost His faith. His was a crisis of courage that shattered his pride.
Like the other disciples, Peter first received the Holy Spirit on the evening of the Lord’s resurrection (John 20:21-23) and after that, he was a different person, even to his manner of speaking. No more a brash, prideful fisherman, he became an eloquent preacher of the gospel. Peter is a prime example of the Holy Spirit’s ability to work wonders in the life of a willing believer.