Don Johnson

Act 14:14
But when the apostles Barnabas and Paul heard of it, they tore their garments and rushed out into the crowd, crying out,

Rom 16:7 on Andronicus and Junia

Gal 1:19
But I saw none of the other apostles except James the Lord’s brother.

infers that James, brother of Jesus, was an apostle.

1Th 1:1

Paul, Silvanus, and Timothy, To the church of the Thessalonians in God the Father and the Lord Jesus Christ: Grace to you and peace.
1Th 2:6
Nor did we seek glory from people, whether from you or from others, though we could have made demands as apostles of Christ.

taken together infers that either Silvanus or Timothy was an apostle and perhaps both.

Rev 21:14
And the wall of the city had twelve foundations, and on them were the twelve names of the twelve apostles of the Lamb.

The point is there are the 12 and then there are other apostles. Apostle is a minitry gift from the Spirit.

Apostle means “sent out one” so it depends who is doing the sending.

Act 1:20
“For it has been written in a scroll of [the] Psalms: ‘Let his residence become desolate, and let no [one] be dwelling in it’; and ‘Let another take his position of overseer.’ [Psalm 69:25; 109:8]

Act 1:21
“Therefore, it is necessary of the men having accompanied us in every time in which the Lord Jesus came in and went out among us-

Act 1:22
having begun from the baptism [or, immersion, and throughout book] of John until the day which He was taken up from us-[for] one of these to become a witness with us of His resurrection.”

Act 1:23
And they put forward two: Joseph, the one being called Barsabas, who was surnamed Justus, and Matthias.

Act 1:24
And having prayed, they said, “You Lord, knower of the hearts of all [people], disclose which one of these two You chose
Act 1:25

Act 1:26
And they gave [fig., cast] their lots, and the lot fell on Matthias, and he was numbered with the eleven apostles.

The use of the word “numbered” strongly indicates that he became the 12th apostle.

No one else makes a claim to be the 12th apostle. Acts 1 also shows they searched the Scriptures and prayed and acted based on these, with NO indication of God’s disapproval.

Mathias is not mentioned by name, but there are later verses that discuss all the apostles doing so and so, so it is implied that he is one of these now 12.
to receive the share of this ministry and apostleship, from which Judas turned aside to go to his own place.”