Orlah as the birur of good from evil

במד' וכי תבואו כו' ונטעתם כו'.

In the Midrash: "And when you come [into the land]... and you shall plant..." (Vayikra 19:23).

The Sefas Emes opens with the mitzvah of orlah — the prohibition of a tree's fruit during its first three years — as the Midrash expounds it.

כי הנה אחר החטא של אדה"ר נתערב טו"ר בכל כי בוודאי עה"ח ועה"ד אינם ענינים פרטים רק שנמצא מאלה העצים בכל מקום.

For behold, after the sin of Adam HaRishon, good and evil became intermingled in everything — for surely the Eitz HaChaim and the Eitz HaDaas are not particular, isolated matters; rather, there is something of these "trees" in every place.

The Tree of Life and the Tree of Knowledge are not merely two physical plants in Gan Eden — they are universal principles, present in every thing in the world.

והי' הבחירה לבחור בזה או בזה.

And the bechirah (free choice) was to choose this one or that one.

Before the sin, a person faced a clean choice between the Tree of Life and the Tree of Knowledge — good clearly distinct from evil.

וכיון שאכל נעשה כל ההנהגה בבחי' עה"ד טוב ורע.

And once he ate, all of conduct became set in the mode of the Eitz HaDaas of good and evil.

After eating from the Tree of Knowledge, the entire order of the world became one of mixture — good and evil blended together rather than standing apart.

וז"ש ואוכל ואמרו במד' ואוכל עוד.

And this is the meaning of "and I ate," and the Midrash says: "and I will yet eat" (Bereishis Rabbah 19:12).

Chazal read Adam's words "and I ate" as implying an ongoing condition — "and I will continue to eat" — that the mixed state would now persist in the world.

והיינו כנ"ל שידע שנעשה כל ההנהגה בתערובת עה"ד.

And this is as above — that he knew all conduct had become a mixture of the Eitz HaDaas.

Adam recognized that from then on every aspect of life would carry this intermingling of good and evil.

ולכן צריך כל דבר בירור.

Therefore everything requires birur (clarification, sifting).

Because good and evil are now intermixed in all things, the work of avodah is to sift and separate the good from the bad in every matter.

ולכן ג"ש ערלה לברר הטוב מהפסולת.

And therefore there are three years of orlah — to sift the good from the waste.

The three years in which a tree's fruit is forbidden are a process of birur, separating the good fruit from the unfit until it is fit to be eaten.

וכתי' יהי' לכם ערלים.

And it is written: "it shall be for you as forbidden (areilim)."

The Torah commands that the fruit be treated as "sealed" and forbidden during this period of refinement.

כי ע"י שבנ"י כל הנהגה שלהם צריך להיות דבוק בשורש ובג' שני ערלה השורש נסתם לכן וערלתם ערלתו כנ"ל:

For since the entire conduct of Bnei Yisrael must be attached to its root, and during the three years of orlah the root is sealed off, therefore "you shall treat its fruit as orlah," as above.

Because a Yid's every act must be bound to its holy root, and during the tree's first three years that root-connection is not yet "open," the fruit remains forbidden until the birur is complete and it can be drawn up to its source.

Summary: After the sin of Adam HaRishon, the Trees of Life and Knowledge ceased to be isolated objects and became universal principles, so that good and evil are intermingled in everything and all of life now demands birur. The three years of orlah are precisely such a process of sifting good from waste: because every act of Bnei Yisrael must be attached to its holy root, and during those years the root remains sealed, the fruit stays forbidden until it can be refined and elevated to its source.