The setting for this verse: Jesus had his last meal with his friends on Thursday (what some call Maundy Thursday), was crucified on Friday (originally called, God's Friday but later renamed, Good Friday), Easter morning the tomb was empty and it's Easter evening. Jesus' disciples are hiding out of fear and Jesus comes among them and says, "peace".
I don't know that the disciples actually "heard" what Jesus was saying. My experience, it's hard to hear, "peace" when you feel afraid; it's hard to be open when you're hiding behind locked doors.
I wonder how we would respond to Jesus offer of peace. We live in contentious and anxious times, seems like there's a lot of anger floating around. "Peace" doesn't mean a lack of these things but rather- in the midst of these things, in the midst of those trying to get us wrapped up in their anger, we choose compassion, we choose to risk loving others.
Metaphorically you could say that we live in times with a lot of locked doors and windows, shutting out those we don't like or who might think differently than we do. But living behind locked doors makes me wonder...who's really the prisoner? For my part...yes, it's a challenging world we live in but I want to open the doors of my life to fresh air and breezes to blow through (some would say to let the Spirit of God blow through). I want to live in the peace that Jesus offered to his followers.