וַ֠יֹּאמְרוּ הָאֲנָשִׁ֤ים הָהֵ֙מָּה֙ אֵלָ֔יו אֲנַ֥חְנוּ טְמֵאִ֖ים לְנֶ֣פֶשׁ אָדָ֑ם לָ֣מָּה נִגָּרַ֗ע לְבִלְתִּ֨י הַקְרִ֜ב אֶת־קָרְבַּ֤ן יְהוָה֙ בְּמֹ֣עֲד֔וֹ בְּת֖וֹךְ בְּנֵ֥י יִשְׂרָאֵֽל׃
And those men said unto him: ‘We are unclean by the dead body of a man; wherefore are we to be kept back, so as not to bring the offering of the LORD in its appointed season among the children of Israel?’
Read midrashic interpretation of Numbers 9:7: and classical rabbinic exegesis.