The song tells how on Christmas morning, Tommy's father is worried about Tommy's future, and soul. His future is jeopardized due to being deaf, dumb, and blind. The lyrics contrast religious themes such as Christmas and Jesus Christ with Tommy's ignorance of such matters. The rhetorical question, "How can he be saved from the eternal grave?" is asked about Tommy's condition and adds speculation as to the nature of original sin and eternal salvation. In the middle of the song, "Tommy can you hear me?" is repeated, with Tommy responding, "See me, feel me, touch me, heal me." However, Tommy's life changes when he receives a pinball machine and eventually becomes the "Pinball Wizard".
"Christmas" was praised by critics. Richie Unterberger of AllMusic called it an "excellent song."Rolling Stone's Mac Randall said it was one of several "prime Pete Townshend songs" on the album. A review in Life by Albert Goldman considered it beautiful and highlighted the song's "croaking chorus". James Perone said it was "perhaps one of the best sleeper tracks of the collection."