Six or seven years symbolize the correction of six or seven Sefirot of the lower part of the Partzuf (spiritual system). The desires called Jews (Yehudi, from the word “Yihud – unity”) during these six or seven years enter into you so much that now they are fully part of you. They can’t be below you.
Question: What does “your brother is sold to you“ mean?
Answer: Sold means that it fully belongs to you, there is no difference between you, and you have to start working with the desire of the other as your personal part. Caring about him and caring about yourself become one. “You shall send him forth free from you” means that in certain cases he separates from you and becomes an independent soul.
Torah, Deuteronomy 15:13: And when you send him forth free from you, you shall not send him forth empty-handed.
Since there is the birth of a new soul, you have to give it all that is necessary to reach maturity. It should receive fulfillment for the future, for the entire length of the path when it will be correcting itself and will need forces for the correction.
From KabTV Program “Secrets of the Eternal Book” 8/10/2016