| Assistant Pastor and Inner City Missionary | RPCNA, Bronx, NY | 1963–1964 |
| Stated Supply | RPCNA, White Lake, NY | 1964–1965 |
| RPCNA, New Castle, PA | 1965–1967 |
| Staff | IVCF | 1967–1975 |
| Recd. by | PrPH, OPC | 1968 |
| Founder and Director | Philadelphia House, Inc., Philadelphia, PA | 1972–1977 |
| CFM | OPC, Korea | 1977–2000 |
| Assistant Professor | General Assembly Theological Seminary, Seoul, Korea | 1980–1982 |
| Associate Professor Missions | General Assembly Theological Seminary, Seoul, Korea | 1982–1986 |
| Director | Miss. Training Institute of the Pres. General Assembly, Seoul, Korea | 1982–1994 |
| Dean | International Graduate School of Theological of the General Assembly Pres. Theological Seminary (HapDong), Seoul, Korea | 1985–1991 |
| Director | Miss. Training Institute, OPC, Seoul, Korea | 1994–2000 |
| Murdock Memorial OPC, Bancroft, SD | 2005 |