Avraham caused Egyptian Exile

 Ramban (Bereishis 12:10) Know that Abraham our father unintentionally committed a great sin by bringing his righteous wife to a stumbling-block of sin on account of his fear for his life. He should have trusted that G-d would save him and his wife and all his belongings for G-d surely has the power to help and to save. His leaving the Land, concerning which he had been commanded from the beginning, on account of the famine, was also a sin he committed, for in famine G-d would redeem him from death. It was because of this deed that the exile in the land of Egypt at the hand of Pharaoh was decreed for his children. In the place of justice, there is wickedness and sin.