'Weeks' in the Bible

You shall observe and celebrate the Feast of Weeks (Harvest, First Fruits, or Pentecost), the first fruits of the wheat harvest, and the Feast of Ingathering (Booths or Tabernacles) at the year’s end.

But if she gives birth to a female child, then she shall be unclean for two weeks, as during her monthly period, and she shall remain [intimately separated] sixty-six days to be purified from the blood.

‘You shall count from the day after the Sabbath, from the day when you brought in the sheaf (tied bundle of grain) of the wave offering; there shall be seven complete Sabbaths (seven full weeks).

‘You are also to count off seven Sabbaths of years for yourself, seven times seven years, so that you have the time of the seven Sabbaths of years, namely, forty-nine years.

‘Also on the day of the first fruits, when you offer a new grain offering to the Lord at your Feast of Weeks, you shall have a holy [summoned] assembly; you shall do no laborious work.

“You shall count seven weeks for yourself; you shall begin to count seven weeks from the time you first put the sickle to the standing grain.

Then you shall celebrate the Feast of Weeks to the Lord your God with a tribute of a freewill offering from your hand, which you shall give [to Him] just as the Lord your God blesses you;

“Three times a year all your males shall appear before the Lord your God in the place which He chooses, at the Feast of Unleavened Bread (Passover) and at the Feast of Weeks (Pentecost) and at the Feast of Booths (Tabernacles), and they shall not appear before the Lord empty-handed.

a certain number every day, offering them up as Moses commanded for the Sabbaths, the New Moons, and the three annual feasts—the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Booths (Tabernacles).

‘They do not say in their heart,“Let us now fear and worship the Lord our God [with profound awe and reverence],Who gives rain in its season,Both the autumn and the spring rain,Who keeps for usThe appointed weeks of the harvest.”

“Seventy weeks [of years, or 490 years] have been decreed for your people and for your holy city (Jerusalem), to finish the transgression, to make an end of sins, to make atonement (reconciliation) for wickedness, to bring in everlasting righteousness (right-standing with God), to seal up vision and prophecy and prophet, and to anoint the Most Holy Place.

So you are to know and understand that from the issuance of the command to restore and rebuild Jerusalem until [the coming of] the Messiah (the Anointed One), the Prince, there will be seven weeks [of years] and sixty-two weeks [of years]; it will be built again, with [a city] plaza and moat, even in times of trouble.

Then after the sixty-two weeks [of years] the Anointed One will be cut off [and denied His Messianic kingdom] and have nothing [and no one to defend Him], and the people of the [other] prince who is to come will destroy the city and the sanctuary. Its end will come with a flood; even to the end there will be war; desolations are determined.

In those days I, Daniel, had been mourning for three entire weeks.

I ate no tasty food, nor did any meat or wine enter my mouth; and I did not anoint (refresh, groom) myself at all for the full three weeks.