13 What was it that the beloved disciple believed (since v. 7 describes what he saw)? Sometimes it is suggested that what he believed was Mary Magdalene’s report that the body had been stolen. But this could hardly be the case; the way the entire scene is narrated such a trivial conclusion would amount to an anticlimax. It is true that the use of the plural “they” in the following verse applied to both Peter and the beloved disciple, and this appears to be a difficulty if one understands that the beloved disciple believed at this point in Jesus’ resurrection. But it is not an insuperable difficulty, since all it affirms is that at this time neither Peter nor the beloved disciple had understood the scripture concerning the resurrection. Thus it appears the author intends his reader to understand that when the beloved disciple entered the tomb after Peter and saw the state of the graveclothes, he believed in the resurrection, i.e., that Jesus had risen from the dead.

In other versions

Then the other disciple, who had reached the tomb first, also went in, and he saw and believed;

Finally the other disciple, who had reached the tomb first, also went inside. He saw and believed.

The other disciple, who had reached the tomb first, then also went in, saw, and believed.

Then the disciple who had reached the tomb first also went in, and he saw and believed—

So then the other disciple who had come to the tomb first also went in, and he saw and believed.

Then went in also that other disciple, which came first to the sepulchre, and he saw, and believed.

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