Greed does not necessarily accompany envy, but is certainly often does. Envy is unhappiness that someone else has something desirable while you do not. This promotes anger, of course, for the global "unfairness" of this. Envy is the direct opposite of patience and trust in the Lord. Greed is the desire for more, more than one's share. Self-control is obviously lacking here, and again, lack of trust in the Lord's goodness.  When you realize that life is not fair, at all, and you accept this, peace can come to reside in your soul. Trials are sent to us as temptations and lessons, and to bring us closer to God. This is why it is difficult for the wealthy to enter heaven, as spoken by Jesus.