Apollos (Apollōs). Genitive ̇ō Attic second declension. Probably a contraction of Apollonios as D has it here.
An Alexandrian (Alexandreus). Alexander the Great founded this city b.c. 332 and placed a colony of Jews there which flourished greatly, one-third of the population at this time. There was a great university and library there. The Jewish-Alexandrian philosophy developed here of which Philo was the chief exponent who was still living. Apollos was undoubtedly a man of the schools and a man of parts.
A learned man (anēr logios). Or eloquent, as the word can mean either a man of words (like one “wordy,” verbose) or a man of ideas, since logos was used either for reason or speech. Apollos was doubtless both learned (mighty in the Scriptures) and eloquent, though eloquence varies greatly in people’s ideas.
Mighty in the Scriptures (dunatos ōn en tais graphais). Being powerful (dunatos verbal of dunamai and same root as dunamis, dynamite, dynamo) in the Scriptures (in the knowledge and the use of the Scriptures), as should be true of every preacher. There is no excuse for ignorance of the Scriptures on the part of preachers, the professed interpreters of the word of God. The last lecture made to the New Testament English class in Southern Baptist Theological Seminary by John A. Broadus was on this passage with a plea for his students to be mighty in the Scriptures. In Alexandria Clement of Alexandria and Origen taught in the Christian theological school.