After Gabriel guided Rick and company to his church in season 5's "Strangers," Rick took a small crew inside to check out the building before letting the rest come in, and that's when audiences got the first glimpse at a passage that was accidentally quite relevant to what was going on in the world outside. Inscribed above the altar was the traditional communion prayer from John 6:54 ("He who eats my flesh and drinks my blood has eternal life"), which took on an all-new meaning in the age of the undead. Later, when Gabriel shared his wine with the group, he made a gentle joke about how he'd had so few communion takers of late.
Additionally, there were five more Bible verses listed on the hymn boards which, if you look up the corresponding passages, also all reflected upon the biter revolution: Romans 6:4 ("Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life"); Ezekiel 37:7 ("So I prophesied as I was commanded: and as I prophesied, there was a noise, and behold a shaking, and the bones came together, bone to his bone"); Matthew 27:52 ("And the graves were opened; and many bodies of the saints which slept arose"); Revelations 9:6 ("And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them"); and Luke 24:5 ("And as they were afraid, and bowed down their faces to the earth, they said unto them, Why seek ye the living among the dead?").
Gabriel might not have had much experience fighting the undead when the group first met him, but he'd obviously spent a great deal of time determining what his favorite book had to say about them!
