>Angels are ancient beings of great intelligence and wisdom and endowed
>with free will. They are quite able to sin.

This is matter of great religious dogma. I only meant to convey the common belief of the masses in these ideas. Which, to my understanding, is that most people consider angles unable to sin, with rare exceptions, if they believe in those.

>Secondly, historically, the age of reason is seven or eight years or age

I am not familiar with the age of reason. But the Church had the age of marriage at 11 for girls for a very long time, raised in the 19th century to 12, and only after a few scandals did the English Parliament make 16 the law.

>by which time most people are able to tell the difference between fantasy
>and reality and between "right" and "wrong." This is why, for example,
>First Penance and Communion has historically been given at seven.

The problem with this is, that the Church had a different age for marriage, regardless of the age for reason.

>It seems to me that the infantalization of children and young adults in
>the western world by means of a severely protracted "childhood" is a
>relatively recent invention, dating from the Victorian era. It is an
>invention of mass society and industrial economy.

That much is true. For a good book on this subject, try "Men in Wonderland", which covers the raising of the age of marriage at 12 to the Age of consent at 16, due to the middle class in England in the early to mid Vicotorian era.