Reply To: Still bothered by the Hagada

It’s a יתור. If it would only say בעבור זה perhaps we could understand that it refers to the time of קרבן פסח during the day. But it already says ביום ההוא from which we could know that. The extra בעבור זה after already saying ביום ההוא comes to teach us that the time being referred is different from that which we could have understood from either on its own.