Metushelach was the grandfather of Noach.  He lived for 969 years.  

There were seven men whose lives spanned the entire history of man: Metushelach saw Adam; Shem saw Metushelach ; Jacob saw Shem; Amram saw Jacob; Achijah the Shilonite saw Amram; Elijah saw Achijah; and Elijah is still alive (Bava Batra 121b).

Metushelach was perfectly righteous. Whatever came out of his mouth ended with the praise of the Holy One, Blessed is He. He studied nine hundred orders of Mishnah (Yalkut Shimoni, Bereshit 42).

God made for Adam...garments of hide (Genisis 3:21). When Adam [was about to] die, he entrusted [these garments] to Seth, who [in return] gave them to Metushelach. When Metushelach [was about to] die, he gave them to Noach (Bamidbar Rabbah 4:8). 

Metushelach who was a great scholar, warned Noach's father Lemech not to call Noach by his correct name, lest the people of the generation of the Flood kill him with sorcery [which is effective only if the correct name is used]. When he was born, Metushelach named him Noach, but to the child's father he said, "Call him Menachem [publicly]" (Yalkut Shimoni, Berheshit 42).

As long as Metushelach lived, the flood did not come upon the world [in his merit]. And when Metushelach died, it was withheld for another seven days after his death [during which time he was mourned] (Avot d'Rabbi Natan 32:1).

As soon as he died, they heard a great noise in heaven, for [the angels] were eulogizing him. Tears flowed from the eyes of the chayot  onto the place of his death. Seeing that, [mankind] eulogized him on earth, and the Holy One, Blessed is He, delayed the punishment of the generation of the Flood for seven days in reward for eulogizing him (Yalkut Shimoni, Bereshit 42). 

During the seven days of mourning over the righteous Metushelach, the Holy One, Blessed is He, gave them abundant light [as reward for eulogizing him (Eitz Yosef)] (Bereshit Rabah 3:6).        

May the merit of the tzaddik Metushelach  protect us all, Amen.