(a) In an assembly of the members of the early church, Peter reminded the people that the place of Judas, following his suicide after betraying Christ, must be, filled in fulfilment of the scriptures.

(b) Some of the conditions for the election were that
(i) the person must have witnessed the baptism of Jesus by John.
(ii) He must have been a companion of Jesus.
(iii) He must have witnessed Jesus' ministry on earth up to the time he was crucified.
(iv) The person must have witnessed Jesus resurrection. Two men, Barnabas whose surname was Justus and Matthias were presented for the election. The apostles prayed for God's guidance in the selection, cast lots for them and the lots fell on Matthias and he was counted among the twelve apostles.