Catholic Ping!
This writer is not well informed so take it with a grain of salt. Only God has immortality!
According to God's Word, souls do die! We are souls, and souls die. Man is mortal (Job 4:17). Only God is immortal (1 Timothy 6:15, 16). The concept of an undying, immortal soul goes against the Bible, which teaches that souls are subject to death.
Do souls die?
"The soul that sinneth, it shall die." Ezekiel 18:20. "Every living soul died in the sea." Revelation 16:3.
The Angels in Sacred Scripture
Angels in the History of the Church
Angels - in Heaven, on Earth and in Hell
Catholic Q&A: Angels and Demons (Fr. Thomas J. Euteneuer)
Question: “Are there really such things as guardian angels?”