神的肖像及靈魂不朽二個思想是基督宗教人學的基石及關懷的重點。神創造人時以自己的肖像和相似創造人，神賦予人相似他的精神理性。聖經的人觀是完整的人的概念。奧斯定受新柏拉圖主義二元論影響，以人的理性才是神的肖像，身體不包括在內。如此的詮釋與聖經的完整的人的概念不符，為的是要保障靈魂不朽的真理。因著基督宗教為一神論的信仰，是三位一體的神。奧斯定以人是聖三的肖像來詮釋。多瑪斯區別肖像的本質和主體，他肯定理性是人成為神的肖像和相似的本質所在。他接受人是聖三的肖像，但他以人為一位格存有；具理性的自立實體，亦即從人為一位位格來說明人為神的肖像。多瑪斯為完整的人的概念奠定形上基礎，他以亞理斯多德的現實與潛能二變化原理說明在物理層次靈魂與身體組合是現實與潛能的。在形上層次人是由存有現實與本質–潛能的組合，這個存有同時是統一起物理層次組合的靈魂與身體的存有。故人是具理性的完整自立實體，是一位位格。如此，理性是肖像的本質，是人相似神所在，但非完整的實體。又有完整的位格人才是肖像的主體。他不僅解釋了完整的人是神的肖像，且因在形上層次理性所接受到的存有，使其成為在自身的實體，人的靈魂具有不朽的形上基礎。

The ideas of the image of God and the immortality of soul are what concern, and subsequently become the two cornerstones of Christian anthropology. In creating man, God said: “Let us make humans in our image, in the likeness of ourselves.” And humanity is endowed by God with the spiritus which symbolizes the likeness of God’s spirit. The biblical view of humans is a holistic concept of man. Augustine, influenced by Platonic dualism, considers only the mens (intellect) to be the image of God, the body is not included. Such an interpretation is in contrast to the Hebraic idea of psychophysiological organism His purpose is to ensure the immortality of soul. Since the God of Christianity is the Triune God, Augustine takes the Trinity as presenting a key feature of the human image. Aquinas distinguishes the essence of image and the subject of image. He states that the intellect is the essence of a human being, but only a part of that essence. The subject of the image is the whole person; a subsistent substance of rational nature, namely, a person, an individual, or a complete substance. Intellect is a substance in its own right, though not a complete substance. God creates a whole person: an embodied spirit. The whole person is the subject of the image of God. Therefore, the intellect is the essence of the image. God exists analogically in a Personal way: humans also exist in a personal manner, whenever their intellectual activities are practiced. In speaking the intellect is a substance in its own right; it has being, which is the being of the composition of body and soul. Hence, Aquinas provides a metaphysical foundation for the immortality of soul, and at the same time confirms the bibliocal view of the holostic human being.