Verily I say unto you, This generation [genea] shall not pass away, till all be fulfilled.
— Luke 21:32 —
Did Peter believe the end would come in his generation? If he did, why would he say this?
II Peter 3:8-9 But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day. 9The Lord isn't slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
Jesus said,
Mark 13:30 Verily I say unto you, that this generation [genea] shall not pass, till all these things be done.
That one little scripture is what caused the false doctrines of preterism, which claims that all of the prophecies were fulfilled by 70 A.D.
The Greek word "genea" which was translated generation in English doesn't just mean the span of a man's life. It also means an age, or an era, as well as a nation. Obviously it didn't mean the span of that generation because all prophecies are not fulfilled. So choose one of the other definitions of genea. Jesus was saying this current state of the world won't end until every prophecy is fulfilled.
Paraphrased: Verily I say unto you, that this age [genea] shall not pass, till all these things be done.
Ephesians 3:20-21 Now unto him that is able to do exceeding abundantly above all that we ask or think, according to the power that worketh in us, 21Unto him be glory in the church by Christ Jesus throughout all ages [genea], world without end. Amen.
Genea is plural or singular. It can refer to any span of time. It depends on the span of time you are referring to. It could be the span of time from creation to the end of time, or it could be the span of time from Jesus' resurrection till His return, or it could refer to the span of a man's life. It is apparent and obvious that all of these things have not yet taken place. They continue to this day, and there are things that have definitely not yet happened.
Revelation 1:7 Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him. Even so, Amen.
It begins like this.
II Peter 3:8 But, beloved, be not ignorant of this one thing,...
We are given that admonition before we are given this information.
II Peter 3:8 ...that one day is with the Lord as a thousand years, and a thousand years as one day.
It means more than just that God is eternal, so time is irrelevant to Him. It means what it says.
Isaiah 46:9 Remember the former things of old: for I am God, and there is none else; I am God, and there is none like me, Declaring the end from the beginning, and from ancient times the things that are not yet done, saying, My counsel shall stand, and I will do all my pleasure:
How did God "declare the end from the beginning"? By giving us the seven day week as a perpetual reminder. The age or genea of man will be six days or six thousand years. The last, or seventh, day will be the millennial rest of the earth.
So that we won't get discouraged and wonder why it hasn't come yet, He gave us Hosea 6:1-3.
Hosea 6:1-3 Come, and let us return unto the LORD: for he hath torn, and he will heal us; he hath smitten, and he will bind us up. 2After two days will he revive us: in the third day he will raise us up, and we shall live in his sight. 3Then shall we know, if we follow on to know the LORD: his going forth is prepared as the morning; and he shall come unto us as the rain, as the latter and former rain unto the earth.
Hebrews 4:8-10 For if Jesus had given them rest, then would he not afterward have spoken of another day. 9There remaineth therefore a rest to the people of God. 10For he that is entered into his rest, he also hath ceased from his own works, as God did from his.