I would imagine that this question comes from concern over a statement made by Jesus in Matthew 19:
23 And Jesus said to His disciples, "Truly I say to you, it is hard for a rich man to enter the kingdom of heaven."
24 "Again I say to you, 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 there are other statements warning the rich to be found in the New Testament:
1Tim 6:9 -10
But those who want to get rich fall into temptation and a snare and many foolish and harmful desires which plunge men into ruin and destruction.
10 For the love of money is a root of all sorts of evil, and some by longing for it have wandered away from the faith and pierced themselves with many griefs.
Instruct those who are rich in this present world not to be conceited or to fix their hope on the uncertainty of riches, but on God, who richly supplies us with all things to enjoy.
18 Instruct them to do good, to be rich in good works, to be generous and ready to share,
and the rich man is to glory in his humiliation, because like flowering grass he will pass away.
For the sun rises with a scorching wind and withers the grass; and its flower falls off and the beauty of its appearance is destroyed; so too the rich man in the midst of his pursuits will fade away.
However, several rich men are portrayed in a very favorable light in the New Testament:
When it was evening, there came a rich man from Arimathea, named Joseph, who himself had also become a disciple of Jesus.
58* This man went to Pilate and asked for the body of Jesus. Then Pilate ordered it to be given to him.
59* And Joseph took the body and wrapped it in a clean linen cloth,
60* and laid it in his own new tomb, which he had hewn out in the rock; and he rolled a large stone against the entrance of the tomb and went away.
In one of Jesus Parables, God is portrayed as a "rich man"
Lu 16:1 Now He was also saying to the disciples, "There was a rich man who had a manager, and this manager was reported to him as squandering his possessions.
In Luke 16:19, we have the story of the "rich man" and Lazarus. But remember there are two "rich men" in this story, one is Abraham. Abraham was said to be in the presence of God, yet, he was a very rich man in life.
Is it a sin to be rich? The answer is No!