It is not the action of God the Son or God the Holy Spirit. It is the action of God the Father. When God places us, or appoints us, as his sons, it is a legal procedure. You know, we may slip and fall, but God will never abandon us. We always will be his sons.
Some people like to be abandoned.
It helps them, I suppose. They don't believe in the security of the believer. Some people thrive in insecurity, but I thrive in the security of the believer. So I thrive in this idea that adoption is permanent. We discussed this before.