וְאַתָּ֛ה תָּב֥וֹא אֶל־אֲבֹתֶ֖יךָ בְּשָׁל֑וֹם תִּקָּבֵ֖ר בְּשֵׂיבָ֥ה טוֹבָֽה׃
But thou shalt go to thy fathers in peace; thou shalt be buried in a good old age.
Read kabbalistic (mystical) interpretation of Genesis 15:15: and classical mystical sources.