When a person says to you, "I can be good apart from Christ" you immediately know at least one thing about him.
He doesn't really know what he's really like.
We know that because if he understood what he was really like apart from Christ, he would know that being good apart from Christ is impossible.
If you look carefully at the different calls to be good throughout the New Testament you'll notice that there is always a very particular order to the author's argument.
1.) Here is a person dead in sins.
2.) God saves Him.
3.) On the basis of that, they are called to be holy.
The problem with most unbelievers is that they mix up that order. They start with number three. Be good. And if you are good enough, you can go onto number 2 - God will save you and accept you.
One of the reasons they do that is because they fail to appreciate the significance of statement
I'm convinced one of the biggest problems most people have is that they have no real idea what their biggest problem really is. It's not just that before God saved us our actions were wrong, it's that before God saved us we were wrong.
Think about how the Bible describes our pre-salvation condition.
Colossians 1:13, "For He delivered us from the domain of darkness..."
What does that mean? It means that apart from Christ we were in the domain of darkness. And what does that mean? It means we as unsaved people weren't neutral towards God. We belonged to His enemy. We were part of Satan's kingdom.
There are only two kingdoms in the world. There aren't three. There's not the kingdom of Satan, the kingdom of really nice, good, neutral people and the kingdom of Jesus. No there's the kingdom of Jesus and the kingdom of Satan, and a person can only belong to one or the other.
Those who belong to the kingdom of Satan, Paul says, Colossians 1:21, are "alienated and hostile in mind and engaged in evil deeds..." Alienated from who? Ephesians 4:18, "alienated from the life of God..." Hostile to who? God Himself.
That's not just what the unbeliever does, that describes who they are. And obviously they can't get what they do straight until something happens with who they are.
If someone is a spy for Saddam Hussein and has successfully infiltrated th CIA, does the fact that he looks like a CIA agent, dresses like a CIA agent, does some of the work of a CIA agent make him a CIA agent? Does it make him a loyal United States citizen? Of course not. He may be a very good spy and he may look an awful lot like a loyal United States citizen but his allegiance his elsewhere. And until that changes just because he dresses up like a CIA agent and looks like a CIA agent doesn't change the fact that he's not a CIA agent.
Or if someone dies and I am so upset by that fact that I decide to pretend like they are alive, does that change things? If I dress him up in a nice little outfit and I lug him around with me places and I sit him down and I try to feed him dinner, if I get one of those bicycles that has the seat in front and the seat in the back and I tie him to the back, does the fact that he has gone places and that he is going through the motions o fbeing alive, change the fact that he's dead. Obviously not, it's all one big show. There's no life in him and though I may force him to do some of the things that people who are alive do, no one in their right mind would go around saying that because he does some of those things, he really is alive.
Being good while rejecting Christ is impossible because it's only through Christ that we have the ability to do good.