RobertsonArchibald Thomas Robertson in his Robertson Word picturesWord Pictures of the New Testament has a nice explanation,that that the gates of Hades will not be able to overcome or imprison the church .ii.e. " o"O death, where is thy sting, o? O grave, where is thy victory..?" (1 Corinthians 15:55, KJV) because Christ led captivity captive (Ephesians 4:8) when he descended into Hades then rose triumphant from the grave with all the believers who had been confined there.