A couple verses come to mind in the Gospels:
Luke 16:13:
"No servant can serve two masters; for either he will hate the one and love the other, or else he will be devoted to one and despise the other You cannot serve God and wealth."
and
Matthew 6:24:
"No one can serve two masters; for either he will hate the one and love the other, or he will be devoted to one and despise the other You cannot serve God and wealth."
The problem here, as I have heard it put once, is that both God and wealth promise similar things. Happiness, provision, fulfillment, even salvation in a way. You either rely on one or the other, you cannot serve both.
1 Timothy 6:10 also points out that, "...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."
The important thing to remember is that while money its self is not evil, the love of it and pursuit of it leads to all sorts of evils.