Is the Bar Mitzvah the same as the Roman adoption Paul talks about?

Les explains that the word adoption as Paul uses it was practiced in Roman and Greek culture: a child born to husband and wife was put under tutors, educated and trained, and prepared to come in at an equal level with the father, perhaps for business. When the child reached that point, he went through the rites of adoption. The Hebrew cultural counterpart, or what is akin to it, is the Bar Mitzvah at age 14, but Les notes it was not the same category because the Romans and Greeks were in the secular world and were preparing the child to be a co-worker in business. By contrast, Paul teaches that the moment we become a believer, we do not go through years of tutoring and training; we are immediately placed as an heir with the Father and the Son. This is what Ephesians 1:5 means: believers were predestinated not to heaven or hell but to that position with Christ from day one as joint heirs in the process of the adoption. Ephesians 1:11 also speaks of obtaining an inheritance and being joint heirs with Christ; if you are a joint heir, the other parties are yours, and in the secular economy, if the other half passes off the scene, the heir ends up with it.