"But she being instructed before by her mother, said: Give me here in a dish the head of John the Baptist. And the king was struck sad: yet because of his oath, and for them that sat with him at table, he commanded it to be given. And he sent, and beheaded John in the prison.-Matthew 14: 6-11
And his head was brought in a dish: and it was given to the damsel, and she brought it to her mother. And his disciples came and took the body, and buried it, and came and told Jesus."
Caravaggio is known for the deep darkness of his images. Perhaps his most famous image is also a decapitation- 'Judith beheading Holofernes'.