Second appearance to the Apostles. Climax of the Gospel in the Confession of Thomas.
26. After eight days] i.e. on the next Sunday, both Sundays being counted in. Here we have the beginning of the observance of the Lord's Day, as the weekly memorial of the Resurrection. The other NT. references are Acts 20:7; 1 Corinthians 16:2; Revelation 1:10. Within] viz. in the same upper room in Jerusalem; not, as some think, in Galilee. Thomas with them] His presence shows a willingness to be convinced. The doors being shut] see on Revelation 1:19.
John 20:26-29
26 And after eight days again his disciples were within, and Thomas with them: then came Jesus, the doors being shut, and stood in the midst, and said,Peace be unto you.
27 Then saith he to Thomas,Reach hither thy finger, and behold my hands; and reach hither thy hand, and thrust it into my side: and be not faithless, but believing.
28 And Thomas answered and said unto him, My Lord and my God.
29 Jesus saith unto him,Thomas, because thou hast seen me, thou hast believed: blessed are they that have not seen, and yet have believed.