The Bible or Tradition, page-49

Christ is the title of Jesus, from the Greek word Khri·stosʹ, which is equivalent to the Hebrew word translated “Messiah,” or “Anointed One.”—Matt 1:16; John 1:41.
The title was given Jesus at the time of his baptism when he was anointed with holy spirit by his Father, Jehovah.
(Matthew 3:16, 17) After being baptized, Jesus immediately came up from the water; and look! the heavens were opened up, and he saw God’s spiritdescending like a dove and coming upon him.  Look! Also, a voice from the heavens said: “This is my Son, the beloved, whom I have approved.”

Jesus followers too were anointed with holy spirit by Jesus at Pentecost 33 CE. From that time onward they became Christians , meaning ''anointed ones''. 3 1/2 years later still gentiles believers were also anointed by holy spirit.
(Acts 10:44-48) While Peter was still speaking about these matters, the holy spirit came upon all those hearing the word.  And the circumcised believers who had come with Peter were amazed, because the free gift of the holy spirit was being poured out also on people of the nations.  For they heard them speaking in foreign languages and magnifying God. Then Peter responded:  “Can anyone deny water to prevent these from being baptized who have received the holy spirit just as we have?”  With that he commanded them to be baptized in the name of Jesus Christ. Then they requested him to stay for some days.

The visible and audible manifestations of holy spirit provided irrefutable evidence that God's special people were no longer fleshly Israel but were instead footstep followers of the ''Anointed One''.
(Hebrews 2:4) while God joined in bearing witness with signs and wonders and various powerful works and with the holy spirit distributed according to his will.

Once that was established these miracles ceased. Wicked men and imposters wasted little time in claiming to be Christians after that.