In this article we have dealt with aspects related to the theology of the Orthodox icon, analyzing both the sacred image that is painted on the icon, the symbols and their importance, but also different classifications of functional and typological nature. The need for knowledge is the basis for respecting the canonicity of the image. It is important to know what the functions of the icon are, and the fact that it acts not only in one direction, from us to the heaven, from the one who prays, to God. In this sense, the status of the icon distinguishes two stages or aspects of its sacramentality, the ascending function, of raising ecclesial and personal prayer to God, and its descending function, of transmitting the sanctifying presence of Christ and the saints to man. There is a whole pneumatology of the icon that is revealed here, in deep agreement with the mystery of Christ. The symbolism and importance of the iconostasis are also other aspects that we addressed in the article, along with the main types of icons, highlighting their importance and necessity. At the end of the article, I chose to discuss non-canonical representations of divinity. Although non-canonical, they are found in many churches and many painters make them, not knowing the theological aspects that underlie the creation of a canonical ic