The Jews therefore sought him on the festival day, and said: Where is he?

the Jews, therefore, were seeking him, in the feast, and said, 'Where is that one?'

Meanwhile the Jews at the Festival were looking for Him and were inquiring, "Where is he?"

At the feast the Jews were looking for him and saying, Where is he?

The Jewish leaders therefore sought him at the feast, and said, 'Where is he?'

Therefore, the Jews were seeking him on the feast day, and they were saying, "Where is he?"

The authorities were looking for him at the Festival and asking 'Where is he?';

The Jews therefore sought him. Here we ought to consider what was the condition of the Church. For the Jews, at that time, gaped for the promised redemption like hungry men; yet, when Christ appears to them, they remain in suspense. Hence arose that murmuring and that variety of opinions. That they whisper secretly is an indication of the tyranny which the priests and scribes exercised over them. It is a shocking exhibition, indeed, that this Church, which was at that time the only Church on earth, is here represented to us as a confused and shapeless chaos. [1] They who rule, instead of pastors, hold the people oppressed by fear and terror, and throughout the whole body there is shameful desolation and lamentable disorder. By the Jews he means the common people, who, having been accustomed for two years to hear Christ, inquire about him, because he does not appear according to his custom. For when they say, Where is he? they describe a man whom they knew, and yet that word shows that they had not yet been earnestly moved, and that they always remained in doubt and suspense.

Footnotes

1 - "Comme un abysme de confusion et disordre;" -- "as a gulf of confusion and disorder."

Then the Jews sought him - By Jews here are to be understood the scribes, Pharisees, and rulers of the people, and not the inhabitants of the province of Judea. It appears, from the following verses, that many of the people were prejudiced in his favor, but they dared not to own it publicly for fear of the Jews, i.e. for fear of the rulers of the people.

Then the Jews sought him at the feast,.... Some to take him and kill him, and others to hear his doctrine, and see his miracles: for all expected him at the feast, knowing it was always his custom, as it was his duty, as an Israelite, to attend at it:
and said, where is he? not naming his name; either through contempt, which might be the case of the far greater part; or through fear of the Jews; or because that he was so well known.

Jews--the rulers.
sought him--for no good end.
Where is He?--He had not been at Jerusalem for probably a year and a half.

The Jews sought him. "The Jews" in John almost always means the ruling class at Jerusalem.
The people means the masses of the Jewish nation. The people were divided in opinion, but dared not express themselves openly until they saw what course the Jews would take.

The Jews - The men of Judea, particularly of Jerusalem.