Q. Please explain the second part of the meaning of "adoption," as it relates to "the placing of a son."
The word ADOPTION as used in this passage (Romans 8:15 KJV) is the Greek word “huiothesis," from huios (mature sons) and thesis (placing). [See #5206 in Stong’s Concordance.]
In the life of a Hebrew male, there were three major events recognized and celebrated by the community. The first event was Circumcision, which occurred when he was only eight days old. This was the moment he was marked as a "covenant man" in Israel.
The second major event was his Bar-Mitzvah, which means "a son accountable." This ceremony, usually scheduled as the son was about to enter puberty, signified 1) when the son became accountable to keep the Commandments of God, and 2)when he became an apprentice to his father in the family business.
The third event described in the Greek text is the "Huiothesia," - or "son placement," - known to most Hebrews as a young man’s "adoption ceremony." When a male child reached what was considered to be the age of maturity (somewhere around 30),
the father placed his hand on his son's head and openly proclaimed, "This is my beloved son in whom I am well pleased!
I bestow upon him now all of my riches and power and authority (through power of attorney), so that he might act on my behalf in all of my affairs."
In the first usage, the son recognizes the Father; in the second the Father recognizes the son. This is a form of one of the Apostle Paul’s themes: “Apprehending that which apprehends us.” (Philippians 3:12)
This concept must register in our consciousness and convictions to bring change.