וַיֹּ֣אמֶר אֲלֵהֶ֗ם בֶּן־מֵאָה֩ וְעֶשְׂרִ֨ים שָׁנָ֤ה אָנֹכִי֙ הַיּ֔וֹם לֹא־אוּכַ֥ל ע֖וֹד לָצֵ֣את וְלָב֑וֹא וַֽיהוָה֙ אָמַ֣ר אֵלַ֔י לֹ֥א תַעֲבֹ֖ר אֶת־הַיַּרְדֵּ֥ן הַזֶּֽה׃
And he said unto them: ‘I am a hundred and twenty years old this day; I can no more go out and come in; and the LORD hath said unto me: Thou shalt not go over this Jordan.
Read kabbalistic (mystical) interpretation of Deuteronomy 31:2: and classical mystical sources.