When Jesus says, “from henceforth, ye know Him and have seen Him”, He was speaking prophetically. He was saying they would see God in the future [Joh 14:7].
The fruit of we’re expected to bear as we abide in Jesus is the fruit of making disciples, therefore this portion of Scripture speaks specifically to ministers—although it also applies to the believers as a whole [Joh 15:1-8].
Jesus sent His apostles to make the disciples of all nations, not the Church as a whole.
The early Church referred to the authority of the apostles.
Even though the Holy Spirit came upon the believers at Pentecost, it was the 12 who led the charge.
It is also seen in the fact that they appointed Matthias to take Judas’ office
If all believers were equal, this wouldn’t have been so.
The Apostle Paul wasn’t Judas’ replacement, Matthias was.
By their criteria, Judas’ replacement had to be one who was with Jesus from the beginning of His ministry to His ascension.