The response to the verses while taking context, order of events in consideration:
Quran (2:244) - Fight in God’s cause is in reference to several things including liberation of the oppressed, meaning the helpless men and women who are yearning and praying for freedom. Freedom from the oppression that Muslims were facing from the Meccan tribes and freedom of speech in doing Dawah i.e. spreading the word of Islam.
If you read the islamic history, you will realize that Muslims were persecuted, humiliated, harassed and tortured to death for no other crime but choosing to believe in the one creater... Women and black people were the most abused believers -Look up 'Bilal' and 'Somia om Amar bin Yasser'. This does NOT refer to fighting and killing innocents. As Quran says:
Fight in the cause of Allah those who fight you, but do not transgress limits; for Allah loveth not transgressors. (PICKTHAL Translation, Quran 2:190)
Fighting is ordained for Muslims in order to defend themselves and their rights, as well as the rights of others. The obligation to physically defend one’s rights. It is sufficient to quote a verse from the Qur’an in this regard:
Let those fight in the way of Allah who sell the life of this world for the other. Whoso fighteth in the way of Allah, be he slain or be he victorious, on him We shall bestow a vast reward. How should ye not fight for the cause of Allah and (for the cause) of the feeble among men and of the women and the children who are crying: Our Lord! Bring us forth from out this town of which the people are oppressors! Oh, give us from thy presence some protecting friend! Oh, give us from Thy presence some defender! Those who believe do battle for the cause of Allah; and those who disbelieve do battle for the cause of idols. So fight the minions of the devil. Lo! the devil’s strategy is ever weak. (4:74 - 4:76)
3:56, and 3:151 are talking about punishment in the afterlife for unbelievers. If you don’t believe in the Islamic account of Hell, not much to worry about, is there?
Quran (4:74) IS MISTRANSLATED ... Don't know if u know Arabic but I do and the word 'Christians is not even mentioned in there ' :S Besides u can't take 74 without linking it to 76 -found above-
Dr. Maher Hathout (Hathout, Jihad vs. Terrorism; US Multimedia Vera International, 2002, p.50) comments on verse 4:76 by saying:
This verse is related to the two preceding verses ) where it was stated that those who fight for God’s cause would be rewarded whether they are victorious or slain. Fighting for God’s cause includes the liberation of the oppressed, meaning the helpless who are yearning for freedom. The believers fight for God’s cause, and the disbelievers fight for the sake of their idols. An idol may be taken conceptually. For example, evil or greed may figuratively be construed as idols.