There are enough evidences in Quran that terrorism is an anathema to Islam. There are a number of evidences / verses from the Quran where it is made clear that terrorism is unwelcome and so is imposition of Islam on non-believers. The killing of non-believers is not permitted either. Infact Quran demands followers of Islam be just even when they are wronged. Below are a few verses from the Quran which point out that terrorism, violence is unacceptable in Islam.
Qur’an 6:151 says, “and do not kill a soul that God has made sacrosanct, save lawfully.” (i.e. murder is forbidden but the death penalty imposed by the state for a crime is permitted). 5:53 says, “… whoso kills a soul, unless it be for murder or for wreaking corruption in the land, it shall be as if he had killed all mankind; and he who saves a life, it shall be as if he had given life to all mankind.”
Qur’an says, “There is no compulsion in religion. The right way has become distinct from error.” (-The Cow, 2:256). Note that this verse was revealed in Medina in 622 AD or after and was never abrogated by any other verse of the Quran. Islam’s holy book forbids coercing people into adopting any religion. They have to willingly choose it.
The Quran says, “But if the enemies incline towards peace, do you also incline towards peace. And trust in God! For He is the one who hears and knows all things.” (8:61) The Quran chapter “The Cow,” 2:190, says, “Fight in the way of God against those who fight against you, but begin not hostilities. Lo! God loveth not aggressors.”
The killing of innocent non-combatants is forbidden. According to Sunni tradition, ‘Abu Bakr al-Siddiq, the first Caliph, gave these instructions to his armies: “I instruct you in ten matters: Do not kill women, children, the old, or the infirm; do not cut down fruit-bearing trees; do not destroy any town . . . ” (Malik’s Muwatta’, “Kitab al-Jihad.”)
Terrorism or hirabah is forbidden in Islamic law, which groups it with brigandage, highway robbery and extortion rackets– any illicit use of fear and coercion in public spaces for money or power. The principle of forbidding the spreading of terror in the land is based on the Qur’an (Surah al-Ma’ida 5:33–34). Prominent [pdf] Muslim legal scholar Sherman Jackson writes, “The Spanish Maliki jurist Ibn `Abd al-Barr (d. 464/ 1070)) defines the agent of hiraba as ‘Anyone who disturbs free passage in the streets and renders them unsafe to travel, striving to spread corruption in the land by taking money, killing people or violating what God has made it unlawful to violate is guilty of hirabah . .
The Qur’an demands of believers that they exercise justice toward people even where they have reason to be angry with them: “And do not let the hatred of a people prevent you from being just. Be just; that is nearer to righteousness.”[5:8]