Old Testament Passages
Thou shalt not avenge, nor bear any grudge against the children of thy people, but thou shalt love thy neighbour as thyself: I am the LORD. (Leviticus 19:18)
And if a stranger sojourn with thee in your land, ye shall not vex him. But the stranger that dwelleth with you shall be unto you as one born among you, and thou shalt love him as thyself; for ye were strangers in the land of Egypt: I am the LORD your God. (Leviticus 19:33-34)
New Testament Passages
Ye are the salt of the earth: but if the salt have lost his savour, wherewith shall it be salted? it is thenceforth good for nothing, but to be cast out, and to be trodden under foot of men. Ye are the light of the world. A city that is set on an hill cannot be hid. Neither do men light a candle, and put it under a bushel, but on a candlestick; and it giveth light unto all that are in the house. Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven. (Matthew 5:13-16)
And the second is like unto it, Thou shalt love thy neighbour as thyself. (Matthew 22:39)
And the second is like, namely this, Thou shalt love thy neighbour as thyself. There is none other commandment greater than these. (Mark 12:31)
Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth: But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also. And if any man will sue thee at the law, and take away thy coat, let him have thy cloke also. And whosoever shall compel thee to go a mile, go with him twain. Give to him that asketh thee, and from him that would borrow of thee turn not thou away. Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy. But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you; That ye may be the children of your Father which is in heaven: for he maketh his sun to rise on the evil and on the good, and sendeth rain on the just and on the unjust. For if ye love them which love you, what reward have ye? do not even the publicans the same? And if ye salute your brethren only, what do ye more than others? do not even the publicans so? (Matthew 5:38-47)
But I say unto you which hear, Love your enemies, do good to them which hate you, Bless them that curse you, and pray for them which despitefully use you. And unto him that smiteth thee on the one cheek offer also the other; and him that taketh away thy cloke forbid not to take thy coat also. Give to every man that asketh of thee; and of him that taketh away thy goods ask them not again. And as ye would that men should do to you, do ye also to them likewise. For if ye love them which love you, what thank have ye? for sinners also love those that love them. And if ye do good to them which do good to you, what thank have ye? for sinners also do even the same. And if ye lend to them of whom ye hope to receive, what thank have ye? for sinners also lend to sinners, to receive as much again. 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. Be ye therefore merciful, as your Father also is merciful. (Luke 6:27-36)
Other New Testament Passages
Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new. And all things are of God, who hath reconciled us to himself by Jesus Christ, and hath given to us the ministry of reconciliation; To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation. Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ's stead, be ye reconciled to God. (2 Corinthians 5:17-20)
I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me. (Galatians 2:20)
What doth it profit, my brethren, though a man say he hath faith, and have not works? can faith save him? If a brother or sister be naked, and destitute of daily food, And one of you say unto them, Depart in peace, be ye warmed and filled; notwithstanding ye give them not those things which are needful to the body; what doth it profit? Even so faith, if it hath not works, is dead, being alone. Yea, a man may say, Thou hast faith, and I have works: shew me thy faith without thy works, and I will shew thee my faith by my works. Thou believest that there is one God; thou doest well: the devils also believe, and tremble. But wilt thou know, O vain man, that faith without works is dead? Was not Abraham our father justified by works, when he had offered Isaac his son upon the altar? Seest thou how faith wrought with his works, and by works was faith made perfect? And the scripture was fulfilled which saith, Abraham believed God, and it was imputed unto him for righteousness: and he was called the Friend of God. Ye see then how that by works a man is justified, and not by faith only. Likewise also was not Rahab the harlot justified by works, when she had received the messengers, and had sent them out another way? For as the body without the spirit is dead, so faith without works is dead also. (James 2:14-26)
The Christian faith should make a significant difference in your life. The passages Galatians 2:20 and 2 Corinthians 5:17-20 show that Christ has given you the power to make changes in your life to live more Christ-like. The passages James 2:14-26 and Matthew 5:13-16 make clear that if you do have faith, it should show up in your works.
The verses Matthew 22:39 and Mark 12:31 show that we are to love our neighbors as ourselves (The two verses from Leviticus show that this is also an Old Testament command and not a new command). These verses do not say to follow them if it is easy. In fact, the Greek verb in both of these verses for "love" is "Αγαπησεις" for agape, or unconditional love.
The passages Matthew 5:38-47 and Luke 6:27-36 show that Christians should go beyond what is normally expected. These passages give examples, obviously during the time of Christ, of going beyond. In fact, today's phrase "go the extra mile" originates from the Matthew 5:38-47 passage. After all, if Christians do what non-Christians typically do, this does nothing to attract people to the faith. For example, if somebody on foot asks me how to get somewhere, instead of merely telling him how to get there, I offer to walk with him there. I have occasionally taken someone who is a stranger home, even if it is significantly out of my way (in one case, it was over 50 miles out of my way) and not charged him anything, although I usually accept any "tips", as I am not aiming to crush an ego or hurt anybody's feelings, but to show that my life with Jesus is different from the norm. When I do things like this, people are really surprised that somebody would do this for them. Remember, actions speak louder than words! Yes, I definitely let them know Who is behind this.
 All scripture references are from the King James Version unless otherwise noted. Please see my about page for why I chose this translation.
 Note that this verse is not a very good translation from Hebrew to English. The Hebrew word translated to "stranger" is better translated as "a person who has converted to Judaism or is in the process of converting to Judaism." Therefore, this passage is not talking about illegal aliens. As the United States is not a theocracy, in today's culture, this "stranger" would, for example, be a foreigner who came here legally.