What does John 20:16 mean?

Mary Magdalene is focused on finding out what happened to Jesus' body. She saw Him murdered and mutilated (John 19:1–4, 18, 34), then hastily buried (Matthew 27:60–61). That was the last time she saw Jesus, and the reason she ran to get help when she came to find the tomb open and empty (John 20:1–10). Mary has no reason to expect to see Jesus alive, let alone there in the garden with her (John 19:40–42). When she turns to leave and hears someone ask what she is doing, her natural response is to assume this is a caretaker (John 20:11–15).

Something in Jesus' tone, or the fact that He uses her name, or the way He pronounces it, gives her a shock of recognition. The emotional impact of this moment is impossible to exaggerate. Modern entertainment is full of surprise guests, or people being revealed after getting new clothes and hairstyles. This appearance by Jesus makes all of those "surprises" look boring by comparison.

Mary's one-word reaction to recognizing Jesus carries layers of importance. John notes that she calls Him "Teacher." Beyond indicating surprise, this also reinforces an important aspect of Jesus' ministry. Women in that era were dismissed as inferior, but those who followed Jesus saw themselves as His students (John 11:28; Luke 10:39). His gospel dispelled the notion that they were lesser than men (Galatians 3:28). The bare fact that women—not men—first realize and proclaim the resurrection of Christ would have been scandalous in the ancient world. This is not a detail someone would invent, given the option.

Jesus' counter-remark in the next verse (John 20:17) suggests Mary tried to embrace Him, or that she threw herself at His feet (Matthew 28:9). That, as well, indicates the powerful emotions of her recognition.