Tzadikim Die early to save them from sin

 Zohar (Bereishis 56b) There is a vanity which is done upon the earth, that there be righteous men unto whom it happeneth according to the work of the wicked, etc.. How there are righteous men to whom it happeneth according to the work of the wicked we have just explained, viz. that because their deeds are good, God removes them from the world before their time and before they become liable to punishment. The rest of the verse, there be wicked men to whom it happeneth according to the work of the righteous, means that God gives them a respite and is long-suffering with them. Thus the good die early in order that they may not degenerate, and the wicked live on in order that they may have a chance to repent, or in order that a virtuous progeny may issue from them. See now, Enoch was virtuous, but God saw that he would degenerate, and therefore gathered him in in time, as one gathers lilies  because of their good scent. And he was not, for God had taken him. This means that he did not live to a great age like his contemporaries, because God took him before his time. R. Eleazar said: God removed Enoch from the earth, and took him up to the highest heavens, and there presented to him wonderful treasures, including forty-five mystical key-combinations of graven letters which are used by the highest ranks of angels, as has been explained elsewhere.