John Lightfoot on Luke 1:2

[Which from the beginning were eyewitnesses and ministers of the word, &c.] If from the beginning have reference to the time wherein Christ published the gospel upon earth, as no one need to doubt, then there is little distinction to be made between eyewitnesses and ministers: for who from that time had been made a minister of the word, that had not been an eyewitness and seen Christ himself? so that we may easily conjecture who are these eyewitnesses and ministers here, viz., the apostles, the seventy disciples, and others that filled up the number of the hundred and twenty, mentioned Acts 1:15.

It is said of Mnason, that he was an old disciple, Acts 21:16. It may be supposed of him, that he had been a disciple from the beginning; that is, from the very time wherein Christ himself published his glad tidings. Those words a good while ago, Acts 15:7, ought to be understood also in this sense.