- Jesus never said it, instead he said "love thy neighbor as thyself." (Matthew 22:39)
- Loving the sinner has a condescending tone that implies superiority of self over "sinner"
- It is difficult for many people to separate sin from sinner... allowing hatred to fester and spread
Each of these reasons has some legitimacy.
Jesus taught that anger with someone else led to great danger (Matthew 5:21-24). He personally showed great compassion to individuals that were condemned as sinners (Luke 19:1-10, John 8:1-11). He frequently preached the importance of mercy, forgiveness, and kindness.
Jesus taught humility. Consider the account of the prayers of the Pharisee and the Publican in Luke 18:10-14. The Pharisee prided himself above the Publican because of his greater diligence in keeping the law of Moses. In spite of this, the humble prayer of the Publican "God be merciful to me a sinner" brought justification to the sinner and not the Pharisee. As Jesus taught: "For whosoever exalteth himself shall be abased; and he that humbleth himself shall be exalted." (Luke 14:11)
Human nature tends to lead people to do ill. Undoubtedly, this contributes to Jesus's analogy of the camel going through the eye of a needle (Matthew 19:24), or encouraging his disciples to deny themselves, take up their cross, and follow him (Matthew 16:24).
I certainly do not wish to take away from the value of these ideas. I do, however, want to point out the problem with this type of thinking. Consider the following hypothetical dialog:
Person 1: We should stop with the "love the sinner, hate the sin."
Person 2: Why?
Person 1: Jesus never said it, instead he said love thy neighbor.
Person 2: He also said "My house shall be called a house of prayer; but ye have made it a den of thieves" as he threw sinners out of the temple.
Person 1: Yes, but he loved them!
Person 2: But perhaps not their sins?
Person 1: Well, calling people sinners implies superiority. You should let God judge!
Person 2: So you're saying that calling people sinners is a sin? And that people who do it are sinners?
Person 1: No! I'm saying that we're not supposed be hateful! I'm saying that if you allow hate in your heart for sin, how can you say there is no hate in your heart for those who sin? We're supposed to love!
Person 2: So it's wrong to hate the idea "love the sinner, hate the sin." Right?
Person 1: I don't hate it, I just want it to stop.
Person 2: Because it is sin?
Person 1: No, because it's hate!
Person 2: And hate isn't a sin?
Person 1: No, it is...
Person 2: Just a sin that bothers you more than other sins?
Person 1: Well, when you put it like that...
There exists a group of people who pride themselves on their refusal to judge... except for those they feel are judgmental. They pride themselves on loving their neighbor, unless they believe their neighbor doesn't love other neighbors the right way.
The hypocrisy of condemning Pharisee-like adherence to a moral code based on behavior because it does not conform to a different Pharisee-like adherence to a moral code based on tolerance should be obvious. In spite of this, I am still surprised by people who do the equivalent of point their finger at someone and shout "You're judgmental, and that makes you bad!"
Calling for an end to "love the sinner, hate the sin" seems to be a well-meaning plea, but it is misguided. Though there is great value in loving neighbor as self... the first and great commandment is to love God. The best way to do this is to keep his commandments. Jesus was very clear about this in all of his teachings, but perhaps no where more than in his admonition "If ye love me, keep my commandments." (John 14:15) When an individual has failed to keep a commandment, repentance is necessary. (Matthew 4:17) While a person who has sinned is still worthy of love, respect, and mercy, the counsel of Christ to the woman caught in adultery is applicable to all: "...go, and sin no more."
While there may not be any single method that is universally helpful in persuading individuals to make better decisions, and it is true that there are some methods that are counter-productive, there is nothing wrong with seeing sin for what it is. It is OK to say that murder is wrong. It is OK to say that a person should honor their marriage vows. It is OK to say that theft is criminal. It is even OK to say a person should not be judgmental. In doing so, it is possible that you are "loving the sinner and hating the sin"... but that is OK too.
Loving the sinner and hating the sin is most beneficial if done introspectively. This is exactly what Paul was expressing in Romans 7 as he declared "For that which I do I allow not: for what I would, that do I not; but what I hate, that do I." (Romans 7:15) Recognizing the need for improvement... recognizing the seriousness of sinful behavior... this can be good if it leads a person to God.
Even when done in the context of helping another, it can be useful. This is what Christ implied with his parables of the lost sheep, the lost coin, and the prodigal son. (Luke 15)
Certainly there is a degree of hypocrisy that a person acquires when they suggest that other people might need to do better (since the same is true for everyone). Still, Jesus inspires missionaries, apostles, and prophets to encourage people to change and improve. (Matthew 28:19-20) As much as some may hate the idea of "love the sinner, hate the sin," it is a perfectly appropriate way of thinking about the responsibility of Christians everywhere, not just to love their neighbor, but to understand that both they and their neighbors need Christ.