Leviticus 19:23-25

 Leviticus 19:23-25 ERV  "In the future, when you enter your country, you will plant many kinds of trees for food. After planting a tree, you must wait three years before you can use any of the fruit from that tree. You must not use that fruit.  24  In the fourth year, the fruit from that tree will be the LORD'S. It will be a holy offering of praise to the LORD.  25  Then, in the fifth year, you can eat the fruit from that tree. And the tree will produce more and more fruit for you. I am the LORD your God.

Leviticus 19:23 MKJV  And when you shall come into the land, and shall have planted all kinds of trees for food, then you shall count the fruit of them as uncircumcised. It shall be uncircumcised three years to you. It shall not be eaten.

"As uncircumcised — That is, as unclean, not to be eaten, but cast away, because the fruit then was less wholesome, and because hereby men were taught to bridle their appetites; a lesson of great use and absolute necessity in a holy life." - Joseph Benson's Commentary on the Old and New Testament

"'Every gardener will teach us not to let fruit trees bear in their earliest years, but to pluck off the blossoms: and for this reason, that they will thus thrive the better, and bear more abundantly afterwards. The very expression, ‘to regard them as uncircumcised,’ suggests the propriety of pinching them off; I do not say cutting them off, because it is generally the hand, and not a knife, that is employed in this operation' [Michaelis]." - Jamieson-Fausset-Brown Commentary

"The fruit tree in its first three years is to be regarded as a male infant during his first eight days (Dillm.), i.e. as unconsecrated. Probably the object was to allow the tree time to become accustomed to the soil, and so to postpone the enjoyment of the fruit till both quantity and quality had had time to develop. This agrees with the direction in Leviticus 19:24 that in the fourth year it should be dedicated to the Lord. Of the manner in which this dedication was to be carried out we are ignorant" - Cambridge Bible for Schools and Colleges

"God would have the first-fruits of their trees, but, because for the first three years they were as inconsiderable as a lamb or a calf under eight days old, therefore God would not have them, for it is fit he should have every thing at its best; and yet he would not allow them to be used, because his first-fruits were not as yet offered: they must therefore be accounted as uncircumcised, that is, as an animal under eight days' old, not fit for any use." - Matthew Henry's Commentary

God, having created the Earth and all it's substance, knows what is best for the fruit trees in order to bear produce. As the Master Gardener, He instructs the Israelites to allow the new fruit trees to grow 3 years before fruit is allowed to be harvested. On the 4th year, the first fruits were to be given to the Lord. Does this mean they had to leave the fruit on the tree a 4th year or did that mean they harvested the fruit but took it to the Tabernacle/Temple or did it mean they harvested it but ate it with thanksgiving to God for His provision and that the wait was over? On the 5th year, the fruit was theirs to harvest.

Israel was to treat the fruits of orchard's as a gift of God, and sanctify the enjoyment of them with thanksgiving. 

Psalms 148:7-13 ERV  Everything on earth, praise him! Great sea animals and all the oceans, praise the LORD!  8  Praise him, fire and hail, snow and clouds, and the stormy winds that obey him.  9  Praise him, mountains and hills, fruit trees and cedar trees.  10  Praise him, wild animals and cattle, reptiles and birds.  11  Praise him, kings of the earth and all nations, princes and all rulers on earth.  12  Praise him, young men and women, old people and children.  13  Praise the LORD'S name! Honor his name forever! His name is greater than any other. He is more glorious than heaven and earth.

What can this show us in our spiritual walk today? God takes time to perfect us. It's not our body and not our intellectual mind but the spirit born within us at salvation. Our body and mind will die, must die. It will be raised to join our eternal spirit but it will die in weakness first. But our spirit is eternal and will grow and strengthen. God is most concerned with this growth. He takes the time and His Wisdom to grow us to a spiritual maturity that will then be healthy and able to produce good fruit. We should cooperate with this time of growth by reading His Word, praying and learning all we can about Him. We should also learn to praise and worship Him as a thank offering. Then we should see healthy fruit naturally forming in us. God, as the Master Gardener, is working on us as His fruit tree. The church is His orchard (or vineyard, as the comparisons expand) with trees growing at different stages as people are saved. You will always have those in the beginning years of their spiritual journey as well as those who should have matured and begun bearing fruit. You will have some that are needing more pruning back and more time while others seem to mature a little faster. But the wise Gardener knows what each fruit tree (or vine) needs in order to get it where He wants it to be.