ἀριθμός

Luke 22:3 ἀριθμοῦ number

Then Satan entered Judas Iscariot, who was one of the Twelve.

Here: 'Number.' Luke uses this word where Mark simply says 'one of the Twelve.' It makes the point that Judas was formally counted in a fixed, chosen roster, and Acts 1:17 picks it up again ('he was numbered among us').

John 6:10 ἀριθμὸν number

“Have the people sit down,” Jesus said. Now there was plenty of grass in that place, so the men sat down, about five thousand of them.

Here: A Greek idiom meaning 'with respect to number', i.e. 'in number'. It presents the figure as a count or reckoning.

Acts 4:4 ἀριθμὸς number

But many who heard the message believed, and the number of men grew to about five thousand.

Here: A tally or headcount. It carries the flavour of Israel's census lists and of the promise that the people would become numerous.

Acts 5:36 ἀριθμὸς number

Some time ago Theudas rose up, claiming to be somebody, and about four hundred men joined him. He was killed, all his followers were dispersed, and it all came to nothing.

Here: "A number": a countable group.

Acts 6:7 ἀριθμὸς number

So the word of God continued to spread. The number of disciples in Jerusalem grew rapidly, and a great number of priests became obedient to the faith.

Here: The headcount. Acts keeps track of numbers (2:41; 4:4; 5:14) to show a real, visible community in the city.

Acts 11:21 ἀριθμὸς number

The hand of the Lord was with them, and a great number of people believed and turned to the Lord.

Here: A 'number' of people, meaning a crowd you could count. Luke likes to report growth in numbers (compare Acts 4:4; 6:7).

Acts 16:5 ἀριθμῷ in number

So the churches were strengthened in the faith and grew daily in numbers.

Here: Dative of respect: the area in which they abounded was headcount. Luke tracks numbers throughout Acts (2:41; 4:4; 6:7; 11:21).

Romans 9:27 ἀριθμὸς number

Isaiah cries out concerning Israel: “Though the number of the Israelites is like the sand of the sea, only the remnant will be saved.

Here: The total count. The phrase 'the number of the sons of Israel' is taken word for word from Hosea 2:1 (1:10 in English Bibles), not from Isaiah.

Revelation 5:11 ἀριθμὸς number

Then I looked, and I heard the voices of many angels encircling the throne, and the living creatures and the elders. And their number was myriads of myriads and thousands of thousands.

Here: "Number", a key word in Revelation (7:4; 9:16; 13:18; 20:8). Here the "number" is given in a phrase that cannot actually be counted.

Revelation 7:4 ἀριθμὸν number

And I heard the number of those who were sealed, 144,000 from all the tribes of Israel:

Here: A number or count. Revelation uses the word for numbers that carry meaning, such as the beast's number in 13:18 and the 200 million horsemen in 9:16. Here it reads like the total of a census.

Revelation 9:16 ἀριθμὸς ἀριθμὸν number

And the number of mounted troops was two hundred million; I heard their number.

Revelation 13:17 ἀριθμὸν number

so that no one could buy or sell unless he had the mark—the name of the beast or the number of its name.

Revelation 13:18 ἀριθμὸν ἀριθμὸς ἀριθμὸς number

Here is a call for wisdom: Let the one who has insight calculate the number of the beast, for it is the number of a man, and that number is 666.

Here: In context (13:17) this is the number of a name. Because Greek and Hebrew letters also served as numerals, every name had a numerical total.

Revelation 15:2 ἀριθμοῦ number

And I saw something like a sea of glass mixed with fire, beside which stood those who had conquered the beast and its image and the number of its name. They were holding harps from God,

Here: The numerical value of the beast's name (13:17-18), worked out by adding up the letters, since Greek and Hebrew letters were also used as numerals. It was a mark of belonging to the beast.

Revelation 20:8 ἀριθμὸς number [is]

and will go out to deceive the nations in the four corners of the earth—Gog and Magog—to assemble them for battle. Their number is like the sand of the seashore.

Here: Their count, the size of the host.