>>23354590>>517103848>a guardian angel is only mentioned once,Psalm 90 in the Septuagint is the daily Orthodox prayer for your Guardian Angel's protection
Apostle Paul gives several details about the 9 ranks of angels in Ephesians Colossians etc but his disciple St Dionysius the Areopagite (who converted in Acts 17) gives a full expo on what he learned from the Apostle about the angels here:
https://tertullian.org/fathers/areopagite_13_heavenly_hierarchy.htm 