Reflections on the nature of the human person having an individual soul; the nature of God as Trinity; the creation of the world by the Creator acting by analogy as a craftsman; the sustaining of all creatures in being by Being; and the complete summary of human knowledge up to 1270 was the tour de force of Thomas Aquinas.
The theology of Thomas Aquinas, in particular his Doctrine of Creation, became the theology of the Catholic Church up to recent times. All priests were instructed according to the teachings of Thomas Aquinas up to Vatican II.
The thought of Thomas Aquinas, for which he fought many battles with his contemporary Catholic Latin theologian scholars, became the basis to concepts behind Western Civilization. I say this because it was he who recognized human persons both male and female as individuals possessing free will and the right to make choices in life.
Thomas Aquinas worked on rational thought, defining what things actually are. His personal faith, however, was completely given to the love of God, to the Person of Jesus Christ and the sanctifying influence of the Holy Spirit. The object of his writing was to glorify God as well as to promote the common good of society.
I am posting this article and series of blog posts on The Principles of Creation website because it explains, in the words of Thomas Aquinas, how God as Trinity created life. God who is principle made things according to their various principles.