Three times after His resurrection Jesus appeared to very close friends who did not recognize Him. There may be more than one reason they couldn't , but, what is common to each of these situations? Disappointment!
In each of the three episodes the text either confirms or implies that disappointment played a significant role in those who met Jesus after His resurrection and yet did not readily recognize him . Luke 24 chronicles the story of Cleopas and his companions as they sadly trod the road from Jerusalem to Emmaus. Jesus intrudes into their narrative completely unrecognized and they are ‘sad and gloomy’. Jesus, as only he can, through questioning conversation and revelation eventually unravels their disappointment, they recognize him and he’s gone. Poof!
Mary,(Magadalene I think), returned to the empty tomb disappointed and broken hearted when two angels asked her why she was crying. (Even the angels see things differently than we do with our limited earthly viewpoint!?! They knew the time of heartache was over. Jesus was alive!) Mary’s lament was that she couldn't locate ‘the dead Jesus’ when behind her stood the ‘Live Jesus’, yet she too didn’t recognize Him. Once again, just as in Luke 24, Jesus asks questions until Mary’s illusion of the ‘still dead’ Jesus evaporates in the face of the Living One! Disappointment eradicated!
Simon Peter had the same experience with Jesus after his betrayal, disappointment, and seaside restoration recorded in John 21. Three times Jesus asked each person questions that dissipated their disappointment and confusion. Often Jesus doesn't settle our issues by answering our questions. He asks us His questions and gives us Himself!