We will begin to shed some light on the subject by examining the preparations made by Yaakov Avinu when he fled from his brother Eisav. Instead of going directly to Charan, he first secluded himself in the Beis Midrash of Eiver for fourteen years studying Torah day and night. Rashi points this out in his commentary at the end of parshas Toldos. His source is the Gemara (Megillah 17a): "דתניא היה יעקב בבית עבר מוטמן ארבע עשרה שנה"—for it was taught in a Baraisa: Yaakov was hidden away in the Academy of Eiver fourteen years. Rashi also points this out when the Torah informs us that Yaakov slept at the site of the future Mikdash (Bereishis 28, 11): “And he lay down in that place”—this expresses exclusion; in that place he lay down; however, during the fourteen years that he served in the house of Eiver, he did not lay down at night, because he engaged in Torah-study.
The commentaries are perplexed by this comment. After all, throughout the 63 years that Yaakov grew up and lived with his parents, Yitzchak and Rivkah, he studied in the Beis Midrash of Shem and Eiver. As it is written (ibid. 25, 27): "ויעקב איש תם יושב אהלים"—and Yaakov was a wholesome man, abiding in tents. Rashi explains that this refers to the tents of Shem and Eiver. This begs the question: Why did Yaakov Avinu see fit to spend another fourteen years studying in the Beis Midrash of Eiver before going to Charan?
We find an intriguing answer to this question in the sacred words of the Imrei Yosef (Vayeitzei). During those fourteen years, Yaakov Avinu worked on perfecting the seven midos. During the first seven years, he learned how to annul the negative aspects of the seven midos; whereas during the second seven years, he learned how to use them for the sake of kedushah. Hence, he remained there specifically fourteen years.
