The plate was not part of the early collections or sales and is probably not in existence.

Luke 24 and John 20, verses 19-29
After His resurrection Jesus appeared to all his disciples, except Thomas. When Thomas later learned about the encounter he stated not to believe in a resurrection until he had been able to put his hands in the wounds of Christ. Eight days later Christ reappeared and invited him to do just that.

There has been much debate among scholars whether the kneeling person is St. Thomas or St. Peter. In Valerius Röver’s inventory of 1731 the plate was called Christus de sleutels aan Petrus gevende (Christ offering the keys to St. Peter), although even close inspection does not show a sign of any key.
In 1824 De Claussin renamed it The incredulity of Thomas, despite the fact that the person pictured is not touching the wounds.
Tümpel pointed out that Rubens and Rembrandt, in a painting (Bredius 552) had earlier chosen the moment of recognition as more dramatical and meaningful. Weisbach suggested the correct and present title of this etching in 1926, but several experts still have doubts and favour the older title(s).

A painting of 1634 (Bredius 552, Corpus A 90, now in the Poesjkin Museum in Moscow) shows the same theme. There is also a drawing in the Louvre (Benesch 1010) which shows a similar composition in reverse and is called Doubting Thomas, giving support to experts favouring that name for the etching as well.
Another drawing, in the Rijksmuseum (B 869) shows similarity, but is no longer attributed to Rembrandt.

The etching is considered as special by Seidlitz and Singer.
Hinterding points at the sketchy execution of the print, comparable to Christ disputing with the doctors (B 65). Some figures are only indicated in outline.

All authors list one state only.

There are various impressions on Japanese or Chinese paper. Considering the limited number of impressions there is a surprisingly large number (eight) of counterproofs,

Various countermarks (3 ed.); Foolscap with five- and seven-pointed collar (3 ed.).

H 237, BB 56-A, G 68 and 76, M 225, Mz 220, RA 286 bis, Cl 93, W 94, Bl 64, Du 96, CD 197, S 49.
W.Weisbach, Rembrandt, 1926, p. 437; J.Q. Van Regteren Altena in Kunstmuseets Årsskrift 1948, p. 6; Hinterding 2008, p. 195ff; Late Rembrandt p. 186;