Prophet Ibrahim (Abraham) - Abraham Reasons With His Father

All was finished between Abraham and his people and the struggle began. The most amazed and furious was his father (or his uncle who had raised him), for, as it is well known, he not only worshipped idols but sculptured and sold them as well. Abraham felt that it was his duty as a good son to advise his father against this evil so that he could be saved from Allah's punishment.

Being a wise son, he did not make his father feel foolish, nor did he openly laugh at his conduct. He told him that he loved him, thereby hoping to generate fatherly love. Then he gently asked him why he worshipped lifeless idols who could not hear, see, or protect him. Before his father could become angry he hastily added: "0 my father! Verily! There has come to me of knowledge that which came not unto you. So follow me. I will guide you to a Straight Path. 0 my father! Worship not Satan. Verily! Satan has been a rebel against the Most Beneficent (Allah). 0 my father! Verily! I fear lest a torment from the Most Beneficent (Allah) overtake you, so that you become a companion of Satan (in the Hell-Fire)."

He (the father) said: "Do you reject my gods, 0 Abraham? If you stop not (this), I will indeed stone you. So get away from me safely before I punish you." Abraham said: "Peace be on you! I will ask Forgiveness of my Lord for you. Verily! He is unto me, Ever Most Gracious. And I shall turn away from you and from those whom you invoke besides Allah. Surah 19: 43-48

Abraham Debates With the Idolaters
His father's harsh treatment did not stop Abraham from delivering the message of truth. Angry and sad to see people prostrate before idols, he was determined to stamp out these practices and went to the town to debate with the people, knowing full well that he might suffer harm.
Like a wise doctor searching for the cause of a sickness so as to prescribe the proper cure, or like a judge who questions the accused sharply so that he might detect the truth, Abraham asked them: "Do the idols see you when you prostrate before them? Do they benefit you in any way?" They quickly tried to defend their beliefs. They argued that they knew their idols were lifeless but that their forefathers had worshipped them; to them this was proof enough for their belief.
Abraham explained that their forefathers had been wrong. This angered them and they retorted: "Are you condemning our gods and our forefathers? Or are you just joking?"
Abraham showed no fear as he replied: "I am serious. I come to you with a true religion. I have been sent with guidance from our Lord Who alone is worthy of worship, Who is the Creator of the heavens and the earth, and Who regulates all affairs of life, unlike the dumb idols which are just stone and wood."
To convince them that the idols could not harm him, he challenged: "I have already condemned them; if they had any power they would have harmed me by now!"