Mary, Peter & John were all acting upon what they thought they knew – Jesus was dead and in a tomb. In Gospel John’s account of this, there are no angels when they first get to the tomb. In this story, for them to see the vision of Jesus’ resurrection, all they had was faith & belief. They had to focus on what was unseen, not seen.
Jesus' work on the cross may be finished, but His work in us is just beginning. All of us have doubts about a vision for the future. Jesus reveals God’s grace to cancel our doubts. We must have faith in order to see what is unseen and He will reveal where He would have us go next.