Hi Bible4life,
Carter Conlon preached on this topic in [url=http://media.tscnyc.org/mp3/2070610S1.mp3]Digging Up the Old Wells of Abraham[/url]
No doubt he was addressing immediate issues within a congregation of over a hundred nationalities, but you will find a clear explanation of the principle Jesus is putting forth, from the Old Testament, in that sermon.
Here is Luke's rendering of what Matthew quoted:
[color=0000FF]Luke 6:35 But love ye your enemies, and do good, and lend, hoping for nothing again; and your reward shall be great, and ye shall be the children of the Highest: for he is kind unto the unthankful and [to] the evil. [/color]
Paul also talks about this, here:
[color=0000FF]Romans 12:20 Therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head. [/color]
Tyndale's marginal note on 'Coals' explains it this way: this, thou shalt kindle him and make him to love.
People are sometimes hostile through fear. If we are not afraid, and treat them with loving respect, their hostility may well fade away.
'Blessing' is the opposite of 'cursing', and it is God's heart that we bless our fellow men.
Remember that Jesus is reported to have been 'beside himself' in Mark's gospel, when He was healing the multitudes (ch 3). His life - the One who created everything - is the Healing power of God, and God very much wants us to approach Him for healing when we have been wounded by others. But, at the same time, He wants us to extend forgiveness to them, which is possible because through His death He paid not only for our sins, but for theirs, and we have no legitimate reason to hold those sins against them.
If a person whom we have forgiven, never ever repents towards God, or asks our forgiveness, that's okay. Just before that verse in Romans, Paul is urging them not to take revenge on their adversaries, but to 'leave room' for 'the wrath of God' who has famously said 'Vengeance is Mine'.
[color=0000FF]Romans 12:14 Bless them which persecute you: bless, and curse not. 15 Rejoice with them that do rejoice, and weep with them that weep. 16 [Be] of the same mind one toward another. Mind not high things, but condescend to men of low estate. Be not wise in your own conceits. 17 Recompense to no man evil for evil. Provide things honest in the sight of all men. 18 If it be possible, as much as lieth in you, live peaceably with all men. 19 Dearly beloved, avenge not yourselves, but [rather] give place [or, don't give in] unto wrath: for it is written, Vengeance [is] mine; I will repay, saith the Lord. 20 [u]Therefore[/u] if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head. 21 Be not overcome of evil, but overcome evil with good. [/color]
There is also Hebrews 10:30, and one in Deuteronomy (KJV).
I heard a testimony second-hand, yesterday, which illustrates something of this issue.
It came from a Tanzanian Christian, who is married to a Rwandan pastor. The Lord had told them all to stay, even though genocide was going on all around. 9That takes faith!)
Then one day, the Lord said 'Go now', and so she picked up her Bible, her passport, and took her three children by the hands and went into the forest to hide. Four hundred other Christians had also been told by the Lord to 'Go' at the same time, and they lived there under the trees for some weeks.
Then one day, she saw that soldiers had appeared on both sides, and were digging big pits - one on each side - and she knew they were all to be killed, so she motioned to her children to stay quiet, and took them deeper into hiding.
But a young man who cared about her, was worried for her, and came looking for her, and thus drew attention to himself. Soldiers stopped him and asked where he was going. He told them, and they told him to lead them to her, so he went to her last known hiding place - where by now she was no longer. Then the soldiers began kicking him and calling him a liar, and would have beaten him to death, until one of them began slandering God, saying 'Your God is a God of war'.
The lady in hiding (who I haven't mentioned was also heavily pregnant with twins) said that when she heard that, something rose up inside of her and before she knew it, she had stepped out of her hiding place to say 'My God is not a God of war!' So the most senior soldier asked for her papers, and she gave him her Tanzanian passport. Then he named a man, and asked if this was her brother (which it was) and she affirmed it with a 'Yes'.
Then the soldier said 'He was such a great help to my family, although I will be in trouble for this, I'm going to let you all go..!'
And so none of the Christians were killed that day.
The lady testifying said 'So, be nice to non-Chrisitans, because you never know when next they might turn up in your life.'
(The twins are fifteen now.)