In light of Mark 10, how can Christians in good conscience purchase luxury items?

I am satisfied with the answer that Jon Ericson has provided, but I would like to add a couple points. The problem lies with the passage's interpretation by the questioner. This passage is not really addressing wealth at all but rather man's attempt at self-justification before God. Let's view another account of the same story in the context of Luke 18. First, we read three parables.

And he told them a parable to the effect that they ought always to pray and not lose heart. 2 He said, “In a certain city there was a judge who neither feared God nor respected man. 3 And there was a widow in that city who kept coming to him and saying, ‘Give me justice against my adversary.’ 4 For a while he refused, but afterward he said to himself, ‘Though I neither fear God nor respect man, 5 yet because this widow keeps bothering me, I will give her justice, so that she will not beat me down by her continual coming.’” 6 And the Lord said, “Hear what the unrighteous judge says. 7 And will not God give justice to his elect, who cry to him day and night? Will he delay long over them? 8 I tell you, he will give justice to them speedily. Nevertheless, when the Son of Man comes, will he find faith on earth?”

Here, we find that Jesus says that God will give His elect "justice." We can assume from the passage that in this case, "justice" means mercy rather than God's wrath. Why can we say this? Because the "Son of Man" title Jesus speaks of in the next sentence is one describing the office He came to fulfill: a willing sacrifice having been perfect in the flesh, not judge of the earth at that time (John 3:17). However, Jesus poses a pretty strong challenge: "when the Son of Man comes, will He find faith?" It should make us ask: "faith in what or whom?" ...let us continue.

The next parable..

9 He also told this parable to some who trusted in themselves that they were righteous, and treated others with contempt: 10 “Two men went up into the temple to pray, one a Pharisee and the other a tax collector. 11 The Pharisee, standing by himself, prayed thus: ‘God, I thank you that I am not like other men, extortioners, unjust, adulterers, or even like this tax collector. 12 I fast twice a week; I give tithes of all that I get.’ 13 But the tax collector, standing far off, would not even lift up his eyes to heaven, but beat his breast, saying, ‘God, be merciful to me, a sinner!’ 14 I tell you, this man went down to his house justified, rather than the other. For everyone who exalts himself will be humbled, but the one who humbles himself will be exalted.”

The point of this passage demonstrates to us that the tax collector, symbolizing the worst of the most hated amongst society for the way they took advantage of others, is justified because he isn't look to his own merit to satisfy God's wrath. The pharisee is doing the opposite and is condemned.

In the next little bit, we read of the children coming to Jesus...

15 Now they were bringing even infants to him that he might touch them. And when the disciples saw it, they rebuked them. 16 But Jesus called them to him, saying, “Let the children come to me, and do not hinder them, for to such belongs the kingdom of God. 17 Truly, I say to you, whoever does not receive the kingdom of God like a child shall not enter it.”

I've heard countless times that this passage is an admonition not to question the Christian faith or ask any tough questions. It disappoints me to hear these things and makes me want to scream. Such teaching is not of Christ, it's of brain-washing cults!

So what does this passage mean? Remember that it's in the context of people claiming righteousness in themselves rather than God's imputed righteousness. It also says that the parents were brining even their infants to Christ and Christ said "to such belongs the kingdom of heaven." Let me ask this... for what in life does an infant rely on himself, that he might have it? Nothing.

Finally we get to the rich young ruler. For brevity, I won't quote the scripture. Essentially, this rich, powerful man asks Christ how to have eternal life. Christ tells him, in a nutshell, "keep the Jewish law you've been given." The RYR says "I have."

And here is where the RYR's self-righteousness comes through. The Law is a bona fide means of salvation only to those who can keep all of it (see the book of James). In Romans, we read that even though The Law offers a bona fide offer of salvation, its purpose was not to save people by their own righteousness. Its purpose is to stop every mouth, that we would recognize our hopeless estate before God, that nothing Good dwells in us apart from God.

So the RYR was telling Jesus "I've kept The Law. I am righteous," but Jesus knew that this was not the case because the entire purpose of The Law is to prove that you cannot please God in your flesh. So, Christ calls the RYR's bluff and says: "prove it. Sell everything and follow me." ...but the man cannot, because he would lose his power and everything that he believes justifies himself before God would crumble before him.

Materialism is a bad thing, but to claim that this passage is about materialism violates the beauty of the Gospel message in these sections.

wouldn't God rather have us take that money and buy a pallet of food for the local food pantry?

Not neccessarily.

I think it helps to be mindful of the Chinese proverb:

Give a man a fish, he eats for a day. Teach a man to fish, he eats for a lifetime.

And in this respect, many Christians are employed as social workers and at food panties and shelters, trying to help the destitute help themselves.

To your questions about:

Flat screens, cars, riding lawn mowers...

In a capitalist economy, the purchase of such goods keeps the economy running and keeps people employed.

However... If a good Christian has the means, he/she should donate to the Church and feed the poor.

While I'm mindful of tithing guidelines, I think it's difficult to prescribe amounts or wealth thresholds. It's a very subjective decision, and I think that only God is in a position to judge.

Jesus knew the general effects wealth has on people. Many will do evil to retain or avoid material loss as it cuts down their status. Many business owners will find invisible ways of deliberately causing problems to tarnish the image of their competitors, they say that is how the game is played. They will create world wars just to profit from sale of weapons. They will own and support big pharmaceutical institutions that produce drugs worldwide with deadly side effects and claim to be curing diseases. Take a look at politics and politicians worldwide, how many will you consider poor? Yet they still chase them. They think their security and power lies in their wealth. Because of this Jesus said

"For where your treasure is, there will your heart be also." (Luke 12:34).

David, a king with power and wealth, as loyal as he was to God was 'blinded' in conscience when he took his subordinate's wife althoug he had many already. He had to be 'slapped to awaken from sleep' by prophet Nathan and on his awakening...

"And David’s anger was greatly kindled against the man; and he said to Nathan, As the LORD liveth, the man that hath done this thing shall surely die:" (2 Samuel 12:5). ...not knowing he was judging himself. That is what power and wealth makes you. You unable to feel the pain others go through and how evil you can suprisingly be.

However, you should mind the difficulty Jesus stresses on:

"...how hard is it for them that trust in riches to enter into the kingdom of God! " (Mark 10:24).

That means it is possible to be rich and still enter the Kingdom. Men like Job, Solomon and some others you can cite yourself were wealthy, but one would have to be alert all times like they were to put God first and not allow distraction of loyalty and faithfulness to Him.

We are commanded to be generous--not impoverished.

The Question

Your assumption seems tenuous. "Since it's hard for the rich to enter the kingdom of God, but it's not impossible since nothing is impossible with God, how can any Christian ever buy anything that benefits only themselves? Jesus never said "Don't buy anything unless it benefits someone else by meeting their physical needs."

An Example from Jesus' Life

Your question assumes that the highest good that a Christian can do is to meet the physical needs of other people. While this is very honorable and all of us ought to do that, we were not created for that purpose, but for another.

In Mark 14, a woman anoints Jesus with a very expensive perfume:

And while he was at Bethany in the house of Simon the leper, as he was reclining at table, a woman came with an alabaster flask of ointment of pure nard, very costly, and she broke the flask and poured it over his head. Mark 14:3 ESV

Judas the traitor is the one who is indignant about the "waste", since the perfume could have been sold and given to the poor (or used to buy a pallet of food for the local food bank). Jesus rebukes Judas, honoring her for her act of worship and sacrifice.

Generosity--not Poverty

For us too, there are greater things for us to do than to give to the poor. Worshiping God and actively seeking to meet the spiritual needs of a world who does not God is much more significant than merely meeting the temporal needs of people.

We are, indeed, commanded to be generous:

As for the rich in this present age, charge them not to be haughty, nor to set their hopes on the uncertainty of riches, but on God, who richly provides us with everything to enjoy. They are to do good, to be rich in good works, to be generous and ready to share, 19 thus storing up treasure for themselves as a good foundation for the future, so that they may take hold of that which is truly life. 1 Timothy 6:17-19 ESV

Paul does not say, "Command those who are rich to stop being rich." He actually says that they ought to be generous, but also that God provides us with everything to enjoy. He also says not to be their hope in riches. Those who are wealthy should keep a right perspective on worldly goods and be mindful that joy and peace come from God and not wealth.

Conclusion

So, yes, let us all give to those who are actually in need, despite their hard work and responsible living. Let us be very generous towards them. Yet, let us not merely meet the physical needs of the world and ignore their spiritual needs. What nobility can be found in extending a person's life here without also providing them with the knowledge of how to have eternal life? Life on earth is quite short and uncertain, while the next life is forever.

Hmm, how do you get from "it is hard for the rich to enter Heaven" to "a Christian shouldn't buy any luxuries"? I think you need to present some logical argument why that follows.

In practical terms, what do you define as "luxury"? You could survive with some basic food and shelter from the elements. Everything beyond that could be considered "luxuries". You certainly don't need a TV, a cell phone, and a computer to live. You don't need a house or apartment: plenty of people have survived in a cave or a cardboard box under a bridge. Etc.

But I don't know any place in the Bible that says that we should not enjoy the blessings that God has given us. Phillipians 4:11-12, "Not that I speak in regard to need, for I have learned in whatever state I am, to be content: I know how to be abased, and I know how to abound. Everywhere and in all things I have learned both to be full and to be hungry, both to abound and to suffer need." Paul enjoyed abundance when it came, and lived with poverty when that came.

Plenty of places in the Bible describe material blessings as gifts from God. Deuteronomy 28:9-12 "The Lord will establish you as a holy people to Himself, just as He has sworn to you, if you keep the commandments of the Lord your God and walk in His ways. Then all peoples of the earth shall see that you are called by the name of the Lord, and they shall be afraid of you. And the Lord will grant you plenty of goods, in the fruit of your body, in the increase of your livestock, and in the produce of your ground, in the land of which the Lord swore to your fathers to give you. The Lord will open to you His good treasure, the heavens, to give the rain to your land in its season, and to bless all the work of your hand. You shall lend to many nations, but you shall not borrow."

I'm certainly not saying that being a Christian will make you rich. What I am saying is that God blesses some people with with wealth, others he blesses in other ways.

The greedy person's problem is not that he enjoys material things too much. It is that he doesn't enjoy them enough. The problem with greed is that it is never satisfied. Whatever blessings God gives him, the greedy person is never happy. He always imagines that if he had more, THEN he would be happy. But he never is. The ideal is to be content, to enjoy what God has given you, to be satisfied and take the pleasures he lets you have.