Where in the chaisha chumshei torah does it talk about emunah?
Emunah is mentioned concerning Avraham Avinu (Bereishis 15:6). It is also mentioned several (three) times with regard to the nation of Israel as they were redeemed from Egypt (Shemos 4:31; 14:31; 19:9), indicatng the centrality of the concept of faith in the very inauguration of our national being. It is this faith that we seek to instill in ourselves and our children on Seder Night, and it is this faith that forms the very cornerstone of our religion.
Ramban expounds on this concept in his commentary to the end of Parashas Bo, stating that one who is lacking in faith (in the Divine direction of events that pass us by) does not have a portion in the Torah of Moshe.