His works are perfect, Deuteronomy 32,4

The expression:"He is the Rock, his works are perfect, and all his ways are just. A faithful God who does no wrong, upright and just is he", Deuteronomy 32:4; is in the song of Moses.
Deuteronomy means in greek "second law", is a book of the Old Testament; the last book of the Pentateuch (Genesis, Exodus, Leviticus, Numbers, Deuteronomy). The autorship of this book is attributed to Moses.
The affirmation: "His works are perfect" has implications is Christian Theology; although God is the wisdom itself, we know God through his works. Tomas Aquinas affirms: in God are present the perfections of all things, Question 4, About the perfection of God.
This is the starting point of the doctrine of the kingdom of God, remember the teaching of Jesus: "Be perfect, as your heavenly father is perfect", Matthew 5:48. It is called perfect to what, of what it requires its perfections, nothing lacks, Thomas Aquinas, Summa Theologiae.
As work of God we are called to his likeness, to the completeness, to the conformity to Jesus Christ.