The number 1290 refers to a prophetic period of 1290 days mentioned in the book of Daniel (Daniel 12:11), linked to end-time events.
In Daniel 12:11 it says: "From the time that the daily sacrifice is abolished and the abomination that causes desolation is set up, there will be one thousand two hundred and ninety days." The number is interpreted as a prophetic time period marking the interval between the abolition of the temple sacrifice and an eschatological fulfillment. In Jewish and Christian tradition, this number has been linked to end-time calculations and historical events such as Antiochus IV Epiphanes' desecration of the temple, as well as future eschatological expectations. It is closely connected with the following figure of one thousand three hundred and thirty-five days in Daniel 12:12, which promises blessing for those who endure. The difference between the 1290 days and the 1260 days (3½ years) mentioned elsewhere in Daniel and Revelation has been the subject of much discussion. The extra 30 days have been interpreted as a transitional period for cleansing or restoring temple sacrifices. Antiochus IV Epiphanes desecrated the temple in Jerusalem in 167 BC by erecting an altar to Zeus in the temple, an event that many historical-critical scholars regard as the primary context for Daniel's prophecies about "the abomination of desolation".*