15 And in those days Peter stood up in the midst of the disciples (altogether the number of names was about a hundred and twenty), and said, 16 “Men and brethren, this Scripture had to be fulfilled, which the Holy Spirit spoke before by the mouth of David concerning Judas, who became a guide to those who arrested Jesus; 17 for he was numbered with us and obtained a part in this ministry.”
And in those days
“Those days” indicates that the 11 and others stayed in the upper room until they chose the replacement apostle for Judas.
Peter stood up in the midst of the disciples
Peter was the leader and spokesman for the 11. This leadership does not imply that he possessed sole authority over the group.
(altogether the number of names was about a hundred and twenty), and said,
Peter’s first speech was to approximately 120 believers in the upper room.
“Men and brethren, this Scripture had to [divine necessity] be fulfilled,
Peter viewed Scripture as mandating the replacement of Judas by another apostle. He referred to two imprecatory psalms of David (Acts 1:20; cf. Pss 69:25; 109:8). His use of Scripture shows his respect for biblical revelation.
which the Holy Spirit spoke before by the mouth of David concerning Judas,
The Holy Spirit spoke through the mouth of David about the future of Judas.
who became a guide to those who arrested Jesus;
Judas guided the enemies of Christ to the Lord and betrayed Him.
for he was numbered with us and obtained a part in this ministry.”
Judas had a role in the ministry of the 12. For this betrayer to fulfill his role as a “guide,” it was determined that he had a share in their ministry. However, this man was not an authentic believer (Jn 6:64) but a thief (Jn 12:6) and a devil (Jn 6:70-71).
A primary agenda of Christians is to apply Scripture to experience.
There are people among the assembly of Christians who are not authentic Christians. They are wolves in sheep’s clothing. It is particularly sad if a pastor takes the role of a Christian leader when he does not believe in its core teaching (Mt 7:22, 23; Jn 10:28).