Of course these are the words of Thomas who doubted the words of the apostles who told him that Jesus had come to them:
[26] And after eight days again his disciples were within, and Thomas with them. Jesus cometh, the doors being shut, and stood in the midst, and said: Peace be to you. [27] Then he saith to Thomas: Put in thy finger hither, and see my hands; and bring hither thy hand, and put it into my side; and be not faithless, but believing. [28] Thomas answered, and said to him: My Lord, and my God. [29] Jesus saith to him: Because thou hast seen me, Thomas, thou hast believed: blessed are they that have not seen, and have believed.
I believe one can make either gesture or none. The prayer is an act of Faith.