What teachings of Jesus oppose violence?

Answer 1

In Exodus 20, Jesus said (among other commandments), "You shall not murder". That definitely opposes violence. And if you obey "Love the Lord your God, and love your neighbor as yourself", you will be obeying all the other commandments, and that opposes violence as well. Jesus's teachings said to love your enemy, not just those that love you.

Answer 2

According to the Holy Bible, Jesus taught his discipoles to - turn the other cheek!
Another thought:
The definition of a 'pacifist' is 'a person who feels that war and violence are unjustifiable'. Jesus is not a pacifist.
As humans, we cannot be judges over others...we cannot determine who is worthy of death...we don't know the heart. But God does(Hebrews 10:29+30). When God's kingdom was represented by Israel in ancient times, his judgements were righteous. Though Israel was not always obedient, and sometimes fought their OWN 'unlawful' wars, God's sanctified wars of the past were 'righteous', permanently destroying only those who were enemies of God and worthy of execution in God's eyes.(Leviticus 20:10/Psalm 24:8/Exodus 15:3/2 Samuel 5:10/1 Samuel 17:45+47)
Things changed when Jesus, the foretold Messiah, arrived. A Christian's 'war' became spiritual, and no longer fleshly(Ephesians 6:11-13), as God was no longer represented by an earthly nation(Matthew 23:37+38). The Kingdom that Christians were defending was God's heavenly kingdom(John 18:36) which did not include physical fighting(Matthew 26:52/John 18:36). Instead, Jesus taught the need to be peaceable and kind to one another and follow his example of compassion,patience and humility in every day life, teaching others God's will(Ezekiel 3:17+18/Matthew 28:19+20/Matthew 24:14). God, himself, is patient with us giving us every opportunity to grow and learn about him and his purposes(John 17:3/John 3:16). He does not want anyone to die(2 Peter 3:9), but wants us to correct our ways and live(2 Corinthians 7:8-12). In the past, God has never shrunk away from supporting his people in 'righteous' warfare (warfare that HE, God, viewed as righteous). When his time comes to bring about his kingdom effects worldwide, his patience will end, and God's FINAL war will be fought(Psalm 110:4-6)(Revelation 12:7-12)(2 Peter 3:1-18)(1 Thessalonians 5:2)(Daniel 2:44)(Revelation 11:18). Jesus will be his chief executioner, destroying those who have chosen to oppose God's purposes.(Revelation 19:11-16+19-21)(2 Thessalonians 1:6-9)
Though Jesus never got involved in mankind's wars(John 18:36/Matthew 26:52), instructing his followers to do the same, he most certainly will be fully involved in God's war of Armageddon (Revelation 16:14-16) and the final destruction of the wicked(Proverbs 2:21+22). Once God's final war has been fought and won, TRUE peace on earth will last forever (Isaiah 2:4)(Psalm 46:8-10)(Micah 4:3+4)(Revelation 21:3+4)(Psalm 37:10,11,29/Matthew 5:5)(Isaiah 2:4/Micah 4:3) (Psalm 72:7).