'Generation' in the Bible

He groaned and sighed deeply in His spirit and said, “Why does this generation demand a sign? I assure you and most solemnly say to you, no sign will be given to this generation!”

For whoever is ashamed [here and now] of Me and My words in this adulterous and sinful generation, the Son of Man will also be ashamed of him when He comes in the glory of His Father with the holy angels.”

He replied, “O unbelieving (faithless) generation, how long shall I be with you? How long shall I put up with you? Bring him to Me!”

I assure you and most solemnly say to you, this generation [the people living when these signs and events begin] will not pass away until all these things take place.