Abraham (peace be upon him) never lied. Allah informs about this in the Qur'an, and Rasulullah(may peace be upon him) has mentioned this fact in one of his hadith. Only three times he spoke lies but it was truth. First: When the polytheists invited to their festivals, he said, "I am illness." The polytheists thought he was ill and left him alone. He mentioned that in that word his heart was filled with sorrow because of polytheists' shirk. Second: he broke polytheists' all idols and left only one. When the polytheists came and asked "Who did this?" then Abraham showed the only survived idol and said'' The biggest of them did this so ask them why if they can speak''. Third: When he migrated to Egypt with our mother Sarah, he called his wife "my sister" to protect themselves from the oppression of the king of that land. In this way he mentioned the religious brotherhood that all Muslims are brothers and sisters. But he was embarrassed for saying such lies which are outward truth.