Jesus appeared to his disciples multiple times after his resurrection. In the first appearance, they were not sure what to think save for the peace given to them by him and revelation of the scars upon body. After this he gives to them the Holy Spirit that they might be sent out in faith to make forgiveness known through Jesus.

Image: St Thomas touches the Risen Lord, picture taken by Lawrence OP. License CC BY-NC-ND 2.0 (no changes made). Image location: https://www.flickr.com/photos/paullew/14036502503/in/photostream/