You know that you are an apostle when Jesus sends you with power. Note how the “disciples” were soon named “apostles”. It’s a subtle mentioning.
Matthew 10
The Twelve Apostles
1 And when He had called His twelve disciples to Him, He gave them power over unclean spirits, to cast them out, and to heal all kinds of sickness and all kinds of disease. 2 Now the names of the twelve apostles are these: first, Simon, who is called Peter, and Andrew his brother; James the son of Zebedee, and John his brother; 3 Philip and Bartholomew; Thomas and Matthew the tax collector; James the son of Alphaeus, and Lebbaeus, whose surname was[a] Thaddaeus; 4 Simon the Cananite,[b] and Judas Iscariot, who also betrayed Him.
1) Power over Unclean spirits : to cast out demons.
2) Heal sicknesses.
3) Heal disease.
There is a difference between being sick and having a disease. Perhaps one is from the world and the other from the spirit.
The apostles had power over all.
They are named. Then they are sent.