Covetousness

Satan knows this well, and tries to rob us of this joy by stirring up covetousness. So we are exhorted in Heb. 13:5, "Let your conversation [conduct as a Christian] be without covetousness; and be content with such things as ye have: for He hath said, I will never leave thee, nor forsake thee." And again in 1 Tim. 6:7, "For we brought nothing into this world, and it is certain we can carry nothing out.”
But with what am I to be content? Food and clothing. Hear, too, what our Lord teaches as to this in Luke 12, and what we are to consider! We are to consider the ravens and the lilies, and how He feeds the one, and clothes the other (vv. 22-30).
What is covetousness? In Scripture there are different words in the Greek all translated by the same English word "covet" or "covetousness." In Luke 12:15-20 and Heb. 12:15-17 it is "greediness for gain." Then in 1 Cor. 5 we are told to put away, not only a fornicator, or drunkard, or railer as a wicked person, but one greedy for gain—a covetous person. Does not all this show how hateful greediness for gain is to God? It is idolatry (Col. 3:5). How it robs God of His proper place!
It robs the soul of the great gain of godliness with contentment, and the joy of the Father acting a father's part to those who are separate from any unequal yoke with unbelievers! Some lines come before me that illustrate the above, and I pass them on to you:
Overheard in an Orchard
Said the Robin to the Sparrow,
“I should really like to know
Why these anxious human beings
Rush about and worry so.”

Said the Sparrow to the Robin,
“Friend, I think that it must be
That they have no heavenly Father,
Such as cares for you and me!”

The sparrow was wrong, we know. Humans have a heavenly Father, but they do not trust His almighty love and care for them, so they "rush about and worry so.”
Not only does covetousness produce restlessness of soul and worry, it hinders quiet happy communion with the Father and the Son. Joy is lost and there is no strength for either worship or service, except perhaps in a legal way. And the Christian becomes dull and cold and shows little sign of life. Such are seldom heard to open their mouths, either in the worship meeting or the prayer meeting, to God the Father or the Son. Yet the Son says, "Let Me see thy countenance, let Me hear thy voice; for sweet is thy voice, and thy countenance is comely." Sol. 2:14.
If the Christian goes on indulging this spirit of greediness for gain, God tells us that such "fall into temptation and a snare, and into many foolish and hurtful lusts, which drown men in destruction and perdition.... But thou, O man of God, flee these things; and follow after righteousness, godliness, faith, love, patience, meekness. Fight the good fight of faith, lay hold on eternal life." 1 Tim. 6:9-12.