The Amazing Spider-Man, Vol. 1 #259 (1984)

All My Pasts Remembered!
With a little help from the Fantastic Four, Peter Parker has been separated from the suit and is now back in the ol' red-and-blues as he hunts for the Hobgoblin. But it's out of costume where the real revelations await: Mary Jane Watson has known Peter's dual identity for years, and now it's time for her to share her own secrets with him! Meanwhile, Reed Richards continues to study the symbiote - which may be more intelligent than even he realizes!
Release Date: 1984