But, if you want the fruit of the tree to be good, then it is sensible to prune the tree regularly so it does not just grow wild. Pruning of trees is what encourages vigorous growth and the best fruit. As
@Red Sky at Morning is a gardener, he might be able to attest to the positive effects of pruning a tree, as well as the pulling up of the weeds, and why that has to be done.
Learning The Law of The Lord so that it can be meditated upon, amounts spiritually to what pruning does to a tree physically. It also makes us aware of any weeds that may have started to spring up in our spiritual life, so that the weeds can be uprooted. Weeds take away nutrients that would otherwise be available to the tree, for producing good fruit.
The Lord is after all The Divine Gardener, for both our spiritual and physical lives. So it is for our own benefit, that we must allow Him (through His Law and Holy Spirit) to do the necessary pruning and weeding that is so necessary in all of our lives, if we want to be able to grow up straight, and not end up getting weeded out and growing wild.
But if we reject The Law, then we are rejecting the pruning of The Lord that He has declared and therefore intended, for our benefit. If there was never any pruning, then we would just grow wild and could be overtaken by the weeds.
John
15:1 I am the True Vine, and my Father is the husbandman.
15:2 Every branch in me that beareth not fruit He taketh away: and every [branch] that beareth fruit, He pruneth it, that it may bring forth more fruit.
15:3 Now ye are clean through the Word which I have spoken unto you.
15:4 Abide in me, and I in you. As the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me.
15:5 I am the vine, ye [are] the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.
15:6 If a man abide not in me, he is cast forth as a branch, and is withered; and men gather them, and cast [them] into the fire, and they are burned.