וּבַשָּׁנָ֣ה הַחֲמִישִׁ֗ת תֹּֽאכְלוּ֙ אֶת־פִּרְי֔וֹ לְהוֹסִ֥יף לָכֶ֖ם תְּבוּאָת֑וֹ אֲנִ֖י יְהוָ֥ה אֱלֹהֵיכֶֽם׃
But in the fifth year may ye eat of the fruit thereof, that it may yield unto you more richly the increase thereof: I am the LORD your God.
Read kabbalistic (mystical) interpretation of Leviticus 19:25: and classical mystical sources.