St. Stephen was the first Christian martyr and one of the seven deacons who helped the Apostles. He died praying for his executioners; showing his perfect imitation of Christ even unto death. His name is included in the Roman Canon (Eucharistic Prayer I).

And as they were stoning Stephen, he prayed, “Lord Jesus, receive my spirit.” And he knelt down and cried with a loud voice, “Lord, do not hold this sin against them.” (Acts 7:59-60)
~ from the Didache Bible