 According to Athanasius of Alexandria, in the mid-3rd century Pope Dionysius wrote a letter to Dionysius of Alexandria criticizing Sabellius's views on the relations between the Son and the Father, as well as some who attempted to refute Sabellius's views.He quotes parts of Dionysius' letter in "On the decrees of the Council of Nicaea" .In this letter it is clear that Dionysius used the word Trinity (Greek "Trias") to explicate the relations between Father, Son and Holy Spirit