Nehemiah 6:5 Midrash

וַיִּשְׁלַח֩ אֵלַ֨י סַנְבַלַּ֜ט כַּדָּבָ֥ר הַזֶּ֛ה פַּ֥עַם חֲמִישִׁ֖ית אֶֽת־נַעֲר֑וֹ וְאִגֶּ֥רֶת פְּתוּחָ֖ה בְּיָדֽוֹ׃

Then sent Sanballat his servant unto me in like manner the fifth time with an open letter in his hand;

Read midrashic interpretation of Nehemiah 6:5: and classical rabbinic exegesis.