"Then Jesus looked around and said to His disciples, 'How hard it is for those who have riches to enter the kingdom of God!' And the disciples were astonished at His words. But Jesus answered again and said to them, 'Children, how hard it is for those who trust in riches to enter the kingdom of God! It is easier for a camel to go through the eye of a needle than for a rich man to enter the kingdom of God.' And they were greatly astonished, saying among themselves, 'Who then can be saved?' But Jesus looked at them and said, 'With men it is impossible, but not with God; for with God all things are possible'" (Mark 10:23-27).
It is difficult, but not impossible, for the rich to enter God's kingdom. The reason why it is such a challenge for one to be rich and still go to heaven is because the tendency of mankind is to trust in wealth. Judas Iscariot heard these words only a few days (or weeks) before he betrayed the Lord for thirty pieces of silver (cf. Matt. 26:14-16). As a side note, it should be observed that Matthew 19:23,24 clearly shows that the phrases "kingdom of heaven" and "kingdom of God" are equivalent.
Paul elaborates on worldly riches in I Timothy 6:9,10,17-19:
"But those who desire to be rich fall into temptation and a snare, and into many foolish and harmful lusts which drown men in destruction and perdition. For the love of money is a root of all kinds of evil, for which some have strayed from the faith in their greediness, and pierced themselves through with many sorrows...Command those who are rich in the present age not to be haughty, nor to trust in uncertain riches but in the living God, who gives us richly all things to enjoy. Let them do good, that they be rich in good works, ready to give, willing to share, storing up for themselves a good foundation for the time to come, that they may lay hold on eternal life."
Wealth itself is not the problem, but the desire to be rich, the love of money, and believing that wealth can save you are huge problems!
Jesus said in Mark 10:25 - "It is easier for a camel to go through the eye of the needle than for a rich man to enter the kingdom of God." Camels may have been the largest animal known and used by common Jews. The image here is intended to be very vivid. Jesus is representing a very large animal trying to squeeze through an extraordinarily small opening (i.e., the eye of a sewing needle).
There is no reason to understand Jesus as referring to anything other than a real camel and a real needle. Some commentators have tried to explain that the "eye of the needle" refers to a low and narrow gate through which the camel could not go except on its knees (and after its burden had been removed). It is true that there was a gate in Jerusalem named "The Needle's Eye," but there is no evidence that it was called such until after the time of Jesus (perhaps in an effort to soften Jesus' teaching here). Thus, this interpretation is not only without historical foundation, it is also inconsistent with the context that is clearly talking about something impossible for men (cf. Mark 10:26). No one who puts riches above God will enter the kingdom of heaven. He has as much chance of doing so as a camel does of pushing itself through the eye of a sewing needle! This truth applies for anyone who values wealth over God--whether they are rich or merely desire to be such!
The disciples were greatly astonished because it was a common Jewish belief that those who were rich were wealthy because they had God's favor (and thus would certainly be saved). Many believed that to experience riches, earthly honor, and good health could mean only one thing--God favored them for their righteousness. If one was suffering, the common (incorrect) assumption was that it must be because of that individual's wickedness (cf. John 9:2; Job).
Also, the disciples of Jesus envisioned themselves as one day being rich in an earthly Messianic kingdom that they thought Jesus would establish. For Jesus to say that the rich will have a difficult time entering into that kingdom is mind-boggling to them! They are going to have to completely change their way of thinking to understand Jesus' teaching here.
Let it be understood that it is humanly impossible for anyone to save himself in an absolute sense (cf. Mark 10:27). It is God who saves. The truth of God can break the spirit of covetousness, purify the heart by faith, and make the rich humble. It is in this way that the rich man can be saved (though such is impossible for man alone). God has the power to cause a camel to go through the eye of a sewing needle just as He has the power to save men (even rich men) when they respond to the gospel with a living, sacrificial faith. God, through His word, can motivate men to give up all for Christ and find true spiritual freedom (cf. John 8:31,32; II Cor. 5:14,15).