"Joseph called Barsabas, who was surnamed Justus" was among the earliest of the disciples of Christ. He was a witness of all that the apostles themselves had seen "beginning from the baptism of John, unto that same day that He was taken up from us" (see below). When a replacement for Judas was chosen, Justus was one of the two candidates; Matthias was the other. Either could have been chosen, both were worthy, but when the lot was done, Matthias, not Justus, was chosen to be the twelfth apostle.
"Joseph called Barsabas, who was surnamed Justus"
After the ascension of Jesus Christ from the Mount of Olives (shown in the photo, see also The Clouds of Heaven), the apostles set about the commission that the Messiah had assigned to them.
"Then returned they unto Jerusalem from the mount called Olivet, which is from Jerusalem a Sabbath day's journey. And when they were come in, they went up into an upper room, where abode both Peter, and James, and John [see The Inner Circle], and Andrew, Philip, and Thomas, Bartholomew, and Matthew, James the son of Alphaeus, and Simon Zelotes, and Judas the brother of James. These all continued with one accord in prayer and supplication, with the women, and Mary the mother of Jesus [see also What Would Mary Really Say About Idolatry?], and with his brethren."
"And in those days Peter stood up in the midst of the disciples, and said, the number of names together were about an hundred and twenty, Men and brethren, this Scripture [see also Which Bible Did Jesus Use?] must needs have been fulfilled, which the Holy Ghost by the mouth of David spake before concerning Judas, which was guide to them that took Jesus. For he was numbered with us, and had obtained part of this ministry."
"Now this man purchased a field with the reward of iniquity [see also Was Judas Necessary?]; and falling headlong, he burst asunder in the midst, and all his bowels gushed out. And it was known unto all the dwellers at Jerusalem; insomuch as that field is called in their proper tongue, Aceldama, that is to say, The field of blood. For it is written in the book of Psalms, Let his habitation be desolate, and let no man dwell therein: and his bishopric let another take."
"Wherefore of these men which have companied with us all the time that the Lord Jesus went in and out among us, Beginning from the baptism of John [see also The Origin of Baptism], unto that same day that he was taken up from us, must one be ordained to be a witness with us of his resurrection."
"And they appointed two, Joseph called Barsabas, who was surnamed Justus, and Matthias. And they prayed, and said, Thou, Lord, which knowest the hearts of all men, show whether of these two thou hast chosen, That he may take part of this ministry and apostleship, from which Judas by transgression fell, that he might go to his own place. And they gave forth their lots; and the lot fell upon Matthias; and he was numbered with the eleven apostles." (Acts 1:12-26 KJV)
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