(8) Look into THE ARIANS OF THE FOURTH CENTURY. It was first published in 1833. Newman made revisions  and  in 2001 the University of Notre Dame Press
reissued his third edition of 1871. Anglican Archbishop of Wales Rowan Williams
succinctly gave the core of Newman’s doctrine in his INTRODUCTION,
dealing with the ancient church’s disciplina arcani : 

"...particularly as evidenced in Alexandria. Patristic catechesis, he claims, was carefully graded,  beginning with the general principles to do with God’s existence
and the moral law, advancing to more specific instruction in the creed, but reserving
until after baptism a full exposition of the mysteries concerned with salvation, 
sacramental theology and the trinitarian character of God." (p.xxviii; for Newman's own words see pp. 45ff) 

Saint Paul had done much the same with the Athenians on Mars Hill. And so later
would Mateo Ricci, S.J. with 16th century Chinese.