Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside contains messages of condolences and wishes for strength and courage. The church's contact information is included on the back of the envelope.

Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a butterfly with geometric motifs. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a turtle with floral motifs on its shell, feet, and neck. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Card with mosaic pattern evoking a flame on the front cover. The inside contains a note of sympathy from the board and staff of Mazon, as well information about the organization

Hallmark card from a member of St. Peter's Episcopal Church in Londonderry, New Hampshire. The envelope contains the following handwritten message: "With love, and healing thoughts-." The front cover says: "LOVE." The card inside is dated November 1, 2018 and reads: "Dear Congregation- My heart is filled with pain for you. We send you our love, and our hope for healing. Bruce [last name redacted] St. Peter's Episcopal Church. Londonderry, NH."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a leaf with geometric motifs. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Program from the November 4, 2018 Sunday worship at Blessed Sacrament Cathedral in Greensburg, Pa. The program contains a special prayer, titled "A Prayer for our Neighbors," which offers words of support for all the victims of the October 27 attack. Signed by two parishioners, Ed and Camille [last name redacted] on the center left.

Miniature New York State flag. Wrapped around stem of flag is a slip of laminated yellow paper reading, "In Memory of our Brother DAVID ROSENTHAL z''l -- To his family and community we pray Tanuchamo min hashamayim. May God in Heaven comfort you. The Principals, Teachers, Parents, Alumni, and Students of Magen David Yeshivah. Brooklyn, NY." Part of a series of 11 flags, each dedicated to one of the victims. Additional photograph shows the entire set of 11.

Post-it note with handwritten message in red marker. The message reads: "Hate is not welcome here." Tape on the upper edge.

Card from "Julia L." expressing solidarity with the community.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "Know that our loving God is with you all- always. Our love is with all of you hoping you can get through this before [?] God- God will [?] love your deep faith. Know we are here in Pt. Loma CA. Feeling your pain."

Rectangular card from a student at Fountain Valley School in Colorado Springs, Co. Front reads: "Dear members of Tree of Life, I'm from Japan and I am writing this letter because on extremely sad news about Jewish people came up yesterday. I'm feeling awfully sorry for Jewish people. I've been learning about 3 monotheistic re[li]gions from last month, so it also made me feel that I have connection with every single Jewish person.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "Dear Tree of Life Synagogue, We learned in church today, our Pastor Karla lived in the community where the tragic incident happened last week. We feel even more insight and sorrow for all involved. We want to offer our love, empathy, future blessings and also prayers for every family affected. We grieve for you, we pray for you, we pray for us all to be as one, we love you. Your San Diego friends in Christ from Point Loma Community Presbyterian Church.

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of seven children holding hands around a table with a large goblet and loaf of braided bread, and seven doves. The illustration is labeled: "We are people of God's peace." The inside reads: "Tree of Life Members, You are in our thoughts and prayers. -Holy Angels CCD."