Weeks: A Period of Time Consisting of Seven Days
Source: TTT
Leviticus 23:15, 16
From the day after the Sabbath, the day you brought the sheaf of the wave offering, you are to count off seven full weeks. / You shall count off fifty days until the day after the seventh Sabbath, and then present an offering of new grain to the LORD.
Luke 18:12
I fast twice a week and pay tithes of all that I acquire.’