Hebrews 13:1-2 (NIV)
1 Keep on loving one another as brothers and sisters. 2 Do not forget to show hospitality to strangers, for by so doing some people have shown hospitality to angels without knowing it.
2 Corinthians 11:14 (NIV)
14 And no wonder, for Satan himself masquerades as an angel of light.
Ephesians 6:12 (NIV)
12 For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms.
I do believe the Catholic standard for a doctrine are 3 scriptural references Which I have provided.
Is it possible that a doctrine could be started that not all of these individuals that we see walking around the world and assume are people are actually Human Beings?
Hebrews 9:27 (NIV)
27 Just as people are destined to die once, and after that to face judgment,
King Herod and some of the disciples seemed to believe in reincarnation?
Mark 6:14 (NIV)
14 King Herod heard about this, for Jesus name had become well known. Some were saying,[a] John the Baptist has been raised from the dead, and that is why miraculous powers are at work in him.
Mark 8:27-28 (NIV)
27 Jesus and his disciples went on to the villages around Caesarea Philippi. On the way he asked them, Who do people say I am? 28 They replied, Some say John the Baptist; others say Elijah; and still others, one of the prophets.