During Jesus’ maiden intercessory prayer as recorded in John 17, in verse 17, He said “sanctify them by truth, thy word is truth” This them referred to His disciples which included ;
Simon Peter
Andrew
James, son of Alphaeus
James
Matthew
Thomas
John
Philip
Bartholomew
Simon the zealot
Judas, soon of James.
Judas Iscariot is not part of the disciples mentioned because at that time he was doomed for destruction (he was with Jesus’ enemies planning a conspiracy against Him)
In John 17:20, Jesus continued to say that His prayer was not for them alone . So in general Jesus prayed for His disciples as well as believers.
All believers need sanctification by the Word.
God bless you for reading.