הֵ֣ן לְרִ֤יב וּמַצָּה֙ תָּצ֔וּמוּ וּלְהַכּ֖וֹת בְּאֶגְרֹ֣ף רֶ֑שַׁע לֹא־תָצ֣וּמוּ כַיּ֔וֹם לְהַשְׁמִ֥יעַ בַּמָּר֖וֹם קוֹלְכֶֽם׃
Eis que para contendas e rixas jejuais, e para ferirdes com punho iníquo! Jejuando vós assim como hoje, a vossa voz não se fara ouvir no alto.
Mishnah Eruvin
One who finds tefillin should bring them in one pair at a time. Rabban Gamaliel says: two pairs at a time. To what does this apply? To old ones but in the case of new ones he is exempt. If he found them arranged in a set or in bundles he shall wait by them until it is dark and then bring them in. In a time of danger, he should cover them and walk away.