I am so grateful for the book "The Blessed Life" by Robert Morris. I have many quotes and excerpts from the book. Great book on giving and tithing.

Living the Blessed Life: The Principle of Tithing
Theme: To teach people the proper attitude and view of tithing.

As we begin this series of “Living the Blessed Life” my goal is to help you have a proper attitude toward giving unto the kingdom of God. Many times with talk about subjects like tithing, giving, or missions giving we seem to approach in a negative mandated type of attitude. We think about it as an obligation when the Lord wants us think about it as a joy. As an opportunity for God to do something great (blessed) in our lives as surrender part of our income to Him.
In other words I want you to understand the principle of tithing and giving is not LAW but it is LIFE
It should never be that we feel that drudgery of giving. Too me this almost takes away from the purpose. Especially if we are fighting over what to do. As one lady told me, “Pastor I would love to tithe but I look at my money and I say, ‘Give to the church or pay my light bill’”. This is not what God expects.
So over this next few weeks I hope that we have a new attitude of giving. The good news is that most of the principles I am about to give is common to many of your lives. You don’t have a problem with giving. You don’t have a problem with that Pastor preaching about giving. Yet some have a problem of their attitude toward giving.
Some give because they expect something back from the church.
Principles of Tithing
#1 The Principle of the First Fruits
The principle of first fruits is a command from the Lord that all the first born belonged to the Lord
Exo 13:2 "Consecrate to Me all the firstborn, whatever opens the womb among the children of Israel, both of man and beast; it is Mine."

They were either to be sacrificed or redeemed. If they were a perfect sacrifice they were to be sacrificed. If they were blemished they were to be redeemed.

As far as the man was concerened, they became the heir in apparent. In other words they were expected to carry out the work of the Lord for the family.

A. The principle of first fruits is a major principle of the Old Testament

B. This is a principle of faith as a person does not know how many will be born after this.

A person who raises sheep and gives the first born of each sheep to the Lord has no idea how many will be born after this. They have to put their faith in God.
There was much more at stake when Abraham offered his son the Lord. Abraham didn’t know how many more children he would have.
C. This first was to be brought into the House of God
Exodus 23:19 "The first of the firstfruits of your land you shall bring into the house of the LORD your God. You shall not boil a young goat in its mother’s milk.
Pro 3:9 Honor the LORD with your possessions, And with the firstfruits