Luke was a native of Syrian Antioch, a physician by profession, a disciple of the apostles. Later he accompanied Paul until the latter's martyrdom, serving the Lord without distraction, for he had neither wife nor children. He died in Boeotia at the age of eighty-four, full of the Holy Spirit. So then, after two Gospels had already been written - Matthew's in Judea and Mark's in Italy - Luke wrote this Gospel in the region of Achaia, by inspiration of the Holy Spirit. At its outset, he indicated that other Gospels had been written before his on, but that the obligation lay upon him to set forth for the Gentile believers a complete account in the course of his narrative and to do so as accurately as possible. The object of this was that they might not be captivated on the one hand by a love for Jewish fables, nor on the other hand be deceived by heretical and vain imaginations and thus wander from the truth. So, right at the beginning, Luke has handed down to us the story of the birth of John [the Baptist], as a most essential [part of the Gospel story]; for John marks the beginning of the Gospel, since he was our Lord's forerunner and associate both in the preparation of the Gospel and in the administration of baptism and the fellowship of the Spirit. This ministry [of John's] was foretold by one of the Twelve Prophets [i.e. the minor prophets]. Later on, the same Luke wrote the Acts of the Apostles.

Eusebius (AD260-339, bishop of Caesarea and author of The History of the Church) wrote:

Luke, by birth an Antiochene and by profession a physician, was for long periods a companion of Paul and was closely associated with the other apostles as well. So he has left us examples of the art of healing souls which he learnt from them in two divinely inspired books, the Gospel and the Acts of the Apostles. The former, he declares, he wrote in accordance with the information he received from those who from the first had been eye-witnesses and ministers of the word, information which, he adds, he had followed in its entirety from the first. The latter he composed not this time from hearsay but from the evidence of his own eyes. It is actually suggested that Paul was in the habit of referring to Luke's Gospel whenever he said, as if writing of some Gospel of his own: `According to my gospel'.