About Our Lady of Mercy · Potomac, Maryland
Our Lady of Mercy is a Roman Catholic parish in Potomac, Maryland, canonically established in 1959 and part of the Archdiocese of Washington. The parish serves a thriving suburban community with weekend Masses in English and Korean, a daily Mass schedule, and a robust K-8 parish school. Its current church, completed in May 2002, seats 800 worshipers and was inspired by the Renaissance Pazzi Chapel in Florence. Our Lady of Mercy is known for its perpetual Eucharistic Adoration chapel, its 'One Mercy' partnership between the church and school, and active outreach including SOME (So Others Might Eat) and a Baby Bottle Campaign for crisis pregnancy support.
- Established
- 1959
- Patron
- Our Lady of Mercy
- Rector
- Father Mark D. Knestout
- Diocese
- Archdiocese of Washington
Why belong here
Our Lady of Mercy offers a full Catholic life in the heart of Potomac: a brand-new classical-Renaissance church seating 800 with a daily chapel that mirrors the original 1961 building, a K-8 parish school rooted in the founding vision of Fr. Marionneaux, and one of the most distinctive spiritual features in the archdiocese — a perpetually open Eucharistic Adoration Chapel in the Parish House. With weekend Masses in English and Korean, OCIA/Adult Faith Formation, K-8 religious education, a Social Justice & Social Concerns ministry, the Men of Mercy fellowship, and outreach to SOME (So Others Might Eat) and crisis pregnancy centers, the parish pairs traditional devotion with active service. It's a place where families can grow in prayer, knowledge, and service — the school's enduring mission statement — all on one campus.
Mass times at Our Lady of Mercy
Weekly Mass schedule
Confession times
- Sunday: 4:00 PM to 4:50 PM
- Friday: 7:30 AM (after the 7:00 AM Mass) until confessions have ended
- Saturday: 4:00 PM to 4:50 PM
Adoration times
- Perpetual Adoration in the Adoration Chapel in the Parish House — doors open between 8:30 AM and 5:00 PM; call the Parish House for the after-hours access code
- Monday–Friday: 7:30 AM to 8:30 AM (between the 7:00 AM and 8:30 AM Masses)
History of Our Lady of Mercy Parish & School
Although canonically established in 1959, Our Lady of Mercy traces its institutional history to 1953, when founding pastor Fr. Louis E. Marionneaux led parishioners in breaking ground for a parochial elementary school. The school opened that September with 174 students in grades 1-4 under principal Mrs. Hazel Blanchard, and Archbishop Joseph F. Rummel dedicated a combined church-and-classroom building on September 24, 1956. Fr. Andrew Frey arrived as the second pastor in 1964 and served 25 years of physical expansion. Msgr. Frey was succeeded by Fr. Michael Moroney (1987), Fr. Miles Walsh (2001), and Fr. Cleo Milano (2013). The current pastor is Fr. Mark D. Knestout, with Fr. Kyle M. Vance serving as Parochial Vicar.
- 1953 — School opens with 174 students; Mrs. Hazel Blanchard is first principal
- 1954 — School formally dedicated May 2
- 1956 — Archbishop Rummel dedicates the original church/classroom building (September 24)
- 1959 — Parish canonically established
- 1961 — Four Salesian Sisters from Cuba arrive to serve the school
- 1964 — Fr. Andrew Frey becomes second pastor (March 1)
- 1987 — Fr. Michael Moroney begins as third pastor
- 1999 — Original 1961 church (350 seats) is razed
- 2001 — Fr. Miles Walsh becomes fourth pastor
- 2002 — New 800-seat Renaissance-style church completed in May
- 2013 — Fr. Cleo Milano becomes fifth pastor; 'One Mercy' launched in December
- 2016 — 'Traditions for Tomorrow' capital campaign launched
- 2018 — New Lower School building opens August with 21 classrooms
Pastoral Leadership & Parish Staff
Our Lady of Mercy is led by Pastor Fr. Mark D. Knestout ([email protected], ext. 126) with Parochial Vicar Fr. Kyle M. Vance and Permanent Deacon Jason Lising. Patricia Cortez Quiros serves as Assistant to the Pastor. The Parish House is staffed by Kelly Athey and Mary Kate Kassman (administrative), Patty Lovett (Business Manager) and Juliette Kabasinga (Business Assistant Manager), Harlene Stanchfield (Human Resources), and German Lopez (Facilities Manager). Communications is handled by Brenda Hadley and Jennifer Palmiere.
- Rev. Mark D. Knestout — Pastor (ext. 126)
- Rev. Kyle M. Vance — Parochial Vicar
- Deacon Jason Lising — Permanent Deacon
- Patricia Cortez Quiros — Assistant to the Pastor (ext. 118)
- Kelly Athey — Administrative Assistant
- Mary Kate Kassman — Administrative Assistant
- Patty Lovett — Business Manager
- Harlene Stanchfield — Human Resources
- Juliette Kabasinga — Business Assistant Manager
- German Lopez — Facilities Manager
Faith Formation & Religious Education
Our Lady of Mercy offers K-8 Religious Education for parish children. Angelus Virata is the Director of Religious Formation and Education for Children, supported by Kathy Isola as Assistant Director. Catechist volunteers are actively recruited — children of catechists receive free tuition. The program runs through the academic year and is supported through the parish registration system. There are also adult formation tracks described under OCIA and Adult Confirmation below.
- K-8 Religious Education classes on Sundays
- Director: Angelus Virata ([email protected], 301-365-1318 ext. 206)
- Assistant Director: Kathy Isola
- Catechist volunteer opportunities (children of catechists receive free tuition)
Becoming Catholic — OCIA & Adult Sacraments
The Order of Christian Initiation for Adults (OCIA) welcomes those wishing to be baptized or received into the Catholic Church, as well as baptized Catholics preparing to receive Holy Communion and Confirmation. The formal catechumenate runs from late September through the Easter Vigil, with Liturgical Rites of Initiation celebrated at weekend liturgies. A Summer Series (May–July, online) is recommended as a starting point. Adult Catholics seeking only Confirmation may enroll in a six-week preparation series, with the option of being confirmed either at the OLOM Easter Vigil or at the Adult Confirmation Mass at the Cathedral of St. Matthew on Pentecost. Anna LaNave (Pastoral Associate for OCIA/Adult Formation) coordinates both tracks.
- OCIA formal program: late September through Easter Vigil
- Summer Inquiry Series: May–July (online)
- Adult Confirmation: six-week series, confirmed at Easter Vigil or at the Cathedral Pentecost Mass
- Contact: Anna LaNave, [email protected], 301-365-1415 ext. 122
Liturgy & Music
The parish supports a full schedule of liturgical ministers, including those serving the 800-seat worship space and the 80-seat daily chapel that echoes the design of the original 1961 church. The music ministry is led by Director of Music Jayne Traynor Rose, with Alina Belenky serving as Organist. Claudia Adjou-Moumouni serves as Pastoral Assistant for Liturgy. The current church features a choir rehearsal room, stained glass above the sanctuary, and an octagonal steel-framed sanctuary roof supporting a cupola and cross.
- Jayne Traynor Rose — Director of Music
- Alina Belenky — Organist
- Claudia Adjou-Moumouni — Pastoral Assistant, Liturgy
- Choir rehearsal room in the church complex
- Stained glass windows above the sanctuary
Our Lady of Mercy Catholic School
Our Lady of Mercy School is a K-8 parish school whose founding vision traces to Fr. Marionneaux's dream of a place 'where the children of the parish could learn the values of the Church and family while getting an exceptional academic foundation.' Decades later, the school's mission still reads: 'Our Lady of Mercy Catholic School provides foundations for a life of prayer, knowledge, and service.' The school is known for its all-lay faculty tradition (a national first in 1953), its 30-year partnership with the Salesian Sisters (1961–early 1990s), and its state-of-the-art Lower School (Early Childhood through 2nd grade) that opened in August 2018 with 21 classrooms plus art, computer, and innovation labs. Today the school is led by Principal Christine Green, with Jason Knecht as Vice Principal.
- Grades K-8 parish school
- Principal: Christine Green ([email protected])
- Vice Principal: Jason Knecht
- Karen Robertson and Lynne Rutland — School Office
- Mission: 'foundations for a life of prayer, knowledge, and service'
- Lower School (EC-2) opened August 2018 with 21 classrooms, art room, computer lab, innovation lab, conference room, cafeteria
Outreach & Social Concerns
Our Lady of Mercy runs an active Social Justice / Social Concerns Ministry ([email protected]) that includes parish-wide giving campaigns, fellowship, and direct service. Active initiatives include participation in SOME (So Others Might Eat) and a Baby Bottle Campaign supporting the Shady Grove Pregnancy Center. The parish also offers a Men of Mercy fellowship for adult men of the parish.
- Social Justice / Social Concerns Ministry — [email protected]
- SOME (So Others Might Eat) service
- Baby Bottle Campaign for Shady Grove Pregnancy Center
- Men of Mercy — men's fellowship and registration
Architecture of the Current Church
Completed in May 2002 after the razing of the original 1961 church, the present Our Lady of Mercy church was designed by DeLizzio Architects and Planners of Potomac. The classical Renaissance design is modeled on the 15th-century Pazzi Chapel in Florence, Italy, with further influence from chapels designed by Michelangelo. The 800-seat sanctuary roof is framed by a modified octagonal steel arch of 33-inch wide-flange members tapering to a 24-inch-deep, 24-foot-diameter compression ring that supports the cupola and precast cross. The building combines steel frame and load-bearing masonry, with light-gage metal studs spanning between structural members. A stone bell tower, stained glass above the sanctuary, an enlarged gathering area, a prayer garden, a choir rehearsal room, and a small 80-seat daily chapel echoing the original church's design complete the complex.
- Completed: May 2002
- Architect: DeLizzio Architects and Planners
- Seating: 800 (replacing a 350-seat 1961 original)
- Sanctuary roof: modified octagonal steel arch on 24-foot-diameter compression ring with cupola and precast cross
- Daily chapel (80 seats) reflecting the original 1961 design
- Stone bell tower, stained glass, prayer garden, choir rehearsal room
Visit, Contact & Getting Involved
Parishioners and visitors can register as parishioners through the parish website (olom.org/parish-registration). The Parish House is open during office hours and houses the Perpetual Adoration Chapel; call 301-365-1415 for an after-hours adoration access code. For sacramental preparation, faith formation, OCIA, music, school enrollment, and outreach, the parish staff list provides direct email and extension numbers for each ministry. The Archdiocese of Washington notes that the parish facilities are wheelchair accessible.
- Parish registration: olom.org/parish-registration
- Parish Phone: 301-365-1415; Fax: 301-365-3104
- Email: [email protected]
- Address: 9200 Kentsdale Drive, Potomac, MD 20854
- Wheelchair accessible (per the Archdiocese of Washington listing)
Pastors & rectors through the years
- Fr. Louis E. Marionneauxfounding pastor (through early 1960s)
Founding pastor; led parishioners in breaking ground for the school in 1953 and oversaw construction of the original church/classroom building dedicated in 1956.
- Fr. Andrew Frey (later Msgr. Frey)March 1, 1964 – retirement (~1987)
Second pastor; served approximately 25 years, directing expansions and improvements to church and school facilities.
- Fr. Michael MoroneyJune 1987 – circa 2001
Third pastor; launched a 1992 master plan and 1994 capital campaign that produced new classrooms, library, computer lab, science lab and cafeteria (dedicated 1996).
- Fr. Miles Walsh2001 – July 2013
Fourth pastor; continued strong support of the school mission.
- Fr. Cleo MilanoJuly 2013 – (succeeded by current pastor)
Fifth pastor; launched the 'One Mercy' parish/school unity project (2013) and the 'Traditions for Tomorrow' capital campaign (2016); oversaw new Lower School opening in 2018.
- Fr. Mark D. Knestoutpresent
Current pastor.