Acts 1:20

his bishopric--or "charge." The words are a combination of Psa 69:25 and Psa 109:8; in which the apostle discerns a greater than David, and a worse than Ahithophel and his fellow conspirators against David.

The inspired historian begins his narrative of the Acts of the Apostles, I. With a reference to, and a brief recapitulation of, his gospel, or history of the life of Christ, inscribing this, as he had done that, to his friend Theophilus (Act 1:1, Act 1:2). II. With a summary of the proofs of Christ's resurrection, his conference with his disciples, and the instructions he gave them during the forty days, of his continuance on earth (Act 1:3-5). III. With a particular narrative of Christ's ascension into heaven, his disciples' discourse with him before he ascended, and the angels' discourse with them after he ascended (Act 1:6-11). IV. With a general idea of the embryo of the Christian church, and its state from Christ's ascension to the pouring out of the Spirit (Act 1:12-14). V. With a particular account of the filling up of the vacancy that was made in the sacred college by the death of Judas, by the electing of Matthias in his room (Act 1:15-26).

1:20-21 ‘Let someone else take his position’: It was imperative that a replacement be found for Judas so that his position as the twelfth apostle would not remain empty. The new people of God, like Israel, were to have twelve designated and appointed leaders (see Matt 19:28; Luke 22:29-30).