Complex sentence: The Assembly then debated the "descensus" until 17 August, when it was decided that the article be amended to say that the "descensus" simply meant that Christ "continued in the state of the dead" until the resurrection.
Split into simpler sentences: The Assembly then debated the "descensus" until 17 August. It was finally decided that the article should be amended to say that the "descensus" simply meant that Christ "continued in the state of the dead" until the resurrection.