(Mishnah): They pour him the second cup. At this point the son asks. If the son is not capable of asking, the father teaches him -

How is this night different from all other nights? For on all other nights we dip once; on this night, we dip twice.

For on all other nights we eat Chametz and Matzah; on this night we eat only Matzah.

For on all other nights we eat roasted or boiled meat; on this night we eat only roasted meat.

The father teaches his son according to his son's ability to understand.

One begins with disgrace (our forefathers were idolaters) and concludes with praise (Hash-m brought us close to His service and redeemed our forefathers from Egypt). He expounds from (Devarim 26,5), "An Aramean tried to destroy my forefather''; until he finishes expounding the entire section (in the Torah).

R. Gamliel: Whoever does not speak about these three things has not fulfilled his obligation - Pesach, Matzah and Maror -

Pesach - that Hash-m skipped over our forefathers' homes in Egypt.

Matzah - that are forefathers were redeemed from Egypt.

Maror - that the Egyptians embittered our forefathers' lives in Egypt.

In every generation, a person is obligated to view himself as if he left Egypt, as the Pasuk states (Shemos 13, 8), "And you shall tell it to your children on this day saying, 'It is because of this that Hash-m acted for me by taking me out of Egypt.''

We are therefore obligated to thank, to say 'Hallel', to praise, to exalt...to declare His greatness, to the One who did for us all of these miracles, and took us out from slavery to freedom, and let us say before Him Haleluyah''.

(Gemara) Beraisa (R. Chiya): The Torah spoke about four sons - the wise son, the wicked son, the foolish son and the son who cannot ask -

The wise son, what does he say? (Devarim 6, 20), "What are the testimonies, laws and ordinances that Hash-m our G-d commanded us?'' You should respond to him (Shemos 13,14), "With a strong hand Hash-m took us out of Egypt, from the house of bondage''.

The wicked son, what does he say? (Shemos 12, 26), "What is this service to you?'' What is this toil that you are putting on us every year? Since he removed himself from the community, you should respond to him (Shemos 13, 8), "It is because of this that Hash-m acted for me'' - for me he acted, but not for this person. If this person would have been in Egypt, he would never have been worthy of redemption.

The foolish son, what does he say? (Shemos 13, 14), "What is this?'' You should teach the laws of the Pesach that "One may not have Afikoman after the Pesach'' (see Daf 118) - that one should not leave one group and join another group.

The son who cannot ask - you should initiate.

R. Yosa - Our Mishnah also teaches this - If the son does not have understanding, his father teaches him.