Dr. Maher Ayyad, a prominent Christian surgeon in the Gaza Strip, said no was hurt by the bomb that was hurled at the car he was in, but the vehicle, belonging to his brother, sustained damage.
Following Friday's incident, Ayyad, 55, began receiving text messages warning him to stop his evangelical work or face the consequences.
Christians in Gaza have faced increasing persecution since Hamas wrested control of the Strip in June 2007.
Since taking control, Hamas has been instituting sharia (Islamic) law throughout the coastal enclave, which, among other things, forbids any non-Muslim from sharing his or her faith.
In January 2010, Majed El Shafie, president of One Free World International, told CBN News Christians are being attacked on an almost daily basis.
"The Christians in the Palestinian Authority [are] facing persecutions. Their homes, their churches -- they get attacked almost everyday," Shafie said.
Christian schools have also been attacked, vehicles torched, equipment stolen and school personnel threatened.
In October 2007, Islamists murdered Rami Ayad, an Arab Christian who worked at the Palestinian Bible Society.
AP contributed to this report.