SEV Biblia, Chapter 19:3
Entonces dijo: ¿En qu pues sois bautizados? Y ellos dijeron: En el bautismo de Juan.
John Gill's Bible Commentary
Ver. 3. And he said unto them, unto what then were ye baptized ? etc.] The apostle takes it for granted that they were baptized, since they were not only believers, but disciples; such as not only believed with the heart, but had made a profession of their faith, and were followers of Christ; but asks unto what they were baptized; either in whose name they were baptized, since Christian baptism was administered in the name of the Spirit, as well as in the name of the Father and of the Son; or what attended or followed their baptism, seeing sometimes the Holy Ghost fell upon persons, either before baptism, or at it, or after it: and they said, unto Johns baptism ; some think they had never been baptized at all with water baptism, only had received the doctrine preached by John, concerning repentance and remission of sins, and so were baptized unto him, professing the same doctrine he did, just as the Israelites were baptized into Moses; others think they were baptized, but very wrongly, being baptized in the name of John, and not in the name of Jesus Christ; and so, as it was not Christian baptism they had submitted to, it was right to baptize them again: but neither of these are probable, for it is not likely that they should receive Johns doctrine, and not his baptism; that they should be his disciples and followers, and not attend to the more distinguishing branch of his ministry; and it is still more unlikely that they should be baptized in his name, who preached Jesus Christ to his followers, and pointed out to them the Lamb of God, and declared him to be greater than he; it seems rather that they were baptized, and that they were baptized in the name of Christ, as Johns disciples were, as the apostle affirms in the following words.
Matthew Henry Commentary
Verses 1-7 - Paul, at Ephesus, found some religious persons, who looked to Jesus a the Messiah. They had not been led to expect the miraculous powers of the Holy Ghost, nor were they informed that the gospel was especiall the ministration of the Spirit. But they spake as ready to welcome the notice of it. Paul shows them that John never design that those he baptized should rest there, but told them that they should believe of Him who should come after him, that is, on Christ Jesus. The thankfully accepted the discovery, and were baptized in the name of the Lord Jesus. The Holy Ghost came upon them in a surprising, overpowerin manner; they spake with tongues, and prophesied, as the apostles an the first Gentile coverts did. Though we do not now expect miraculou powers, yet all who profess to be disciples of Christ, should be calle on to examine whether they have received the seal of the Holy Ghost, in his sanctifying influences, to the sincerity of their faith. Many see not to have heard that there is a Holy Ghost, and many deem all that is spoken concerning his graces and comforts, to be delusion. Of such it may properly be inquired, "Unto what, then, were ye baptized?" for the evidently know not the meaning of that outward sign on which they plac great dependence.
Greek Textus Receptus
ειπεν 2036 5627 V-2AAI-3S τε 5037 PRT προς 4314 PREP αυτους 846 P-APM εις 1519 PREP τι 5101 I-ASN ουν 3767 CONJ εβαπτισθητε 907 5681 V-API-2P οι 3588 T-NPM δε 1161 CONJ ειπον 2036 5627 V-2AAI-3P εις 1519 PREP το 3588 T-ASN ιωαννου 2491 N-GSM βαπτισμα 908 N-ASN
Vincent's NT Word Studies
3. Unto what (eiv ti). Rev., more correctly, into. See on Matt. xxviii. 19. John. The last mention of John the Baptist in the New Testament. "Here, at last, he wholly gives place to Christ" (Bengel).
Robertson's NT Word Studies
19:3 {Into what} (eis ti). More properly, {Unto what} or {on what basis} (Robertson, _Grammar_, p. 592). Clearly, Paul felt they had received a poor baptism with no knowledge of the Holy Spirit. {John's baptism} (to iwanou baptisma). Last mention of John the Baptist in the N.T. They had been dipped in other words, but they had not grasped the significance of the ordinance.