Just as there was one door to Noach’s ark and the salvation it offered from the waters of the flood, there is only one Door to salvation to save us from the eternal destruction of wickedness that will come at the final judgement.
From the Torah passage נֹחַ Noach (Gen. 6:9–11:32), we see how its main figure tried to warn his generation of the trouble that laid ahead for the earth.
Similarly, Yeshua (Jesus) did the same in His generation, and He has called each generation of His followers to warn their generation of the coming “time of trouble.”
As the proverb says, history may not repeat itself, but it rhymes. And studying the history of the world from the Torah (Genesis, Exodus, Leviticus, Numbers and Deuteronomy) is how we can know what will happen, even if we don’t understand exactly when these things will happen.