Therefore, so that the memory always remain unto generations to come, the obligation for each and every person to recount year after year was established. Even if one is wise and knows the entire Torah. It may not, in any case, be forgotten by our children at any time; were some people exempt from recounting, it might be forgotten. Every Jewish person is able to tell the story, and everybody would feel exempt from recounting it because they already know it. This could eventually lead us to forgetting. Therefore, the obligation for each and every person to recount the story was established, even if one is wise and knows the entire Torah. There can be no better safeguarding of the memory of the Exodus from Egypt than this.