Are we living in a righteous generation? What is the Bible's definition of a generation?
"A masculine noun meaning generation, period of time, posterity, age, time, setting of life. In general, the word indicates the time from birth to death; the time from one's birth to the birth of one's first child; the living adults of a certain time or place; a period as it is defined through major events, persons, behavior, and the spirit of the age. It also marks a duration of time. There is no agreed on length of time which may stretch from twenty to one hundred years, but the word is also used figuratively to mean an indefinite or unending length of time in the past or future. These basic observations can be illustrated from various passages and contexts: the generation of Noah was characterized by wickedness and violence, yet he was a righteous man in his generation (Gen_7:1); Moses spoke of a crooked generation in his day and in the future (Deu_32:5); however, the psalmist spoke of a generation of righteous people (Psa_14:5) and a generation of people who seek the Lord (Psa_24:6). These generations will be blessed by God (Psa_112:2). Generations come and go without interruption (Ecc_1:4)." (The Complete WordStudy Dictionary)
A generation (the period of time for a human's life), Biblically, can be:
(1) 70 years
(2) 80 years
(3) 120 years
"The days of our years are threescore years and ten (seventy years)--or even, if by reason of strength, fourscore years (eighty years); yet is their pride [in additional years] only labor and sorrow, for it is soon gone, and we fly away." (Psalm 90:10 AMP)
"Then the Lord said, My Spirit shall not forever dwell and strive with man, for he also is flesh; but his days shall yet be 120 years." (Genesis 6:3 AMP)