MEDFORD, Mass. — Boston began to say goodbye on Sunday to those it lost last week. Its leaders — religious as well as political — fanned out, in front of naves and cameras, to do what they could to reassure grieving parishioners and constituents that the danger had passed. Or that for those who are gone, “life,” as Cardinal Sean P. O’Malley put it, “is not ended, merely changed.”

Memories were not the only thing etched for some mourners.

As Melanie Fitzemeyer, who baby-sat for Krystle Campbell two decades ago, walked to Ms. Campbell’s wake along with hundreds of others at a brick-and-frame funeral home on Main Street here, she took off her jacket and rolled up her sleeve. Incised on her arm was a two-line tattoo she had gotten the night before, at a parlor owned by one of Ms. Campbell’s cousins.

“Boston Strong,” the top line read in black letters scored into the length of her forearm, the surrounding skin still pink and tender.

“1983 Krystle 2013,” read the bottom.

Ms. Campbell, a 29-year-old restaurant manager, died after last Monday’s bombing at the Boston Marathon from wounds sustained near the finish line of a race she tried to see every year. Ms. Fitzemeyer, 39, knew her longer than most, and remembered her as an exuberant child. “She liked to paint and color and make things,” she said.