Money is spiritual

A steward is someone entrusted with another person's wealth or property and charged with responsibility of managing it in the owner's best interest. - Ben Patterson

A steward is entrusted with sufficient resources and the authority to carry out their designated responsibilities.

As a fundraiser I have come up with my own definition of what stewardship is - stewardship is the conscientious management of things that really matter.

God delegated to us authority over all His creation.

You made him to have dominion over the works of Your hands;
You have put all things under his feet,
All sheep and oxen,
And also the beasts of the field - Psalm 8:6-7

God expects us to use all the resources He gives us to best carry out our responsibilities.  A steward's  primary goal is to be found faithful by their master as the stewards uses the master's resources to accomplish the tasks delegated to them.

Our use of money and possessions is only one aspect of stewardship.  The tabernacle was built by people giving their time, energy, skills, money and possessions.  How we view and handle our money will correspond with how we view and handle our time, talents, family, church, vocation and every facet of life.

Eleven of the thirty-nine parables of Jesus deal with finances and money directly --  

• investment
• indebtedness
• hiring procedures and wage structures
• leasing
• capital, investments, banking, and interest
• money lenders, interest and debt cancellation
• storing up
• architectural planning, building construction and cost analysis
• finding lost money
• wealth, estate planning, spending
• financial management and debt reduction
• wealth and poverty
• giving and greed
• harvest

The parables normally have one central point that should not be obscured by uncertainties about secondary issues - the steward is praised for their shrewdness in using their master's money to invest in His relationships with people.

There will be a day when we will be terminated from this life, a day in which we shall give an account for our stewardship.  Consequently, we should use wisely what little remaining time and influence we have before our term of stewardship is done.

Jesus doesn't tell us to stay away from the mammon of unrighteousness or "worldly wealth," but to use it strategically.

And I tell you [learn from this], make friends for yourselves [for eternity] by means of the [a]wealth of unrighteousness [that is, use material resources as a way to further the work of God], so that when it runs out, they will welcome you into the eternal dwellings. - Luke 16:9

Money can be a tool for Christ.

“He who is faithful in a very little thing is also faithful in much; and he who is dishonest in a very little thing is also dishonest in much." - Luke 16:10

We are continually tested in little things.

God pays a great deal of attention to the "little things." He numbers the hairs on our head, cares for the lilies of the field and is concerned with the fall of a single sparrow.  What we do with the little time, a little talent, and a little money tells God a lot.

Therefore if you have not been faithful in the use of earthly wealth, who will entrust the true riches to you? - Luke 16:11

What are true riches?

Having been faithful in handling our resources in this life, we are granted leadership of others in the next.

And if you have not been faithful in the use of that [earthly wealth]which belongs to another [whether God or man, and of which you are a trustee], who will give you that which is your own? - Luke 16:12