Exodus 4:8

וַיֹּאמֶר יְהוָה לוֹ עוֹד הָֽבֵא־נָא יָֽדְךָ בְּחֵיקֶךָ וַיָּבֵא יָדוֹ בְּחֵיקוֹ וַיּוֹצִאָהּ וְהִנֵּה יָדוֹ מְצֹרַעַת כַּשָּֽׁלֶג

And the LORD said furthermore unto him: ‘Put now thy hand into thy bosom.’ And he put his hand into his bosom; and when he took it out, behold, his hand was leprous, as white as snow.

וַיֹּאמֶר הָשֵׁב יָֽדְךָ אֶל־חֵיקֶךָ וַיָּשֶׁב יָדוֹ אֶל־חֵיקוֹ וַיּֽוֹצִאָהּ מֵֽחֵיקוֹ וְהִנֵּה־שָׁבָה כִּבְשָׂרֽוֹ

And He said: ‘Put thy hand back into thy bosom.—And he put his hand back into his bosom; and when he took it out of his bosom, behold, it was turned again as his other flesh.—

וְהָיָה אִם־לֹא יַאֲמִינוּ גַּם לִשְׁנֵי הָאֹתוֹת הָאֵלֶּה וְלֹא יִשְׁמְעוּן לְקֹלֶךָ וְלָקַחְתָּ מִמֵּימֵי הַיְאֹר וְשָׁפַכְתָּ הַיַּבָּשָׁה וְהָיוּ הַמַּיִם אֲשֶׁר תִּקַּח מִן־הַיְאֹר וְהָיוּ לְדָם בַּיַּבָּֽשֶׁת

And it shall come to pass, if they will not believe even these two signs, neither hearken unto thy voice, that thou shalt take of the water of the river, and pour it upon the dry land; and the water which thou takest out of the river shall become blood upon the dry land.’

וַיֹּאמֶר מֹשֶׁה אֶל־יְהוָה בִּי אֲדֹנָי לֹא אִישׁ דְּבָרִים אָנֹכִי גַּם מִתְּמוֹל גַּם מִשִּׁלְשֹׁם גַּם מֵאָז דַּבֶּרְךָ אֶל־עַבְדֶּךָ כִּי כְבַד־פֶּה וּכְבַד לָשׁוֹן אָנֹֽכִי

And Moses said unto the LORD: ‘Oh Lord, I am not a man of words, neither heretofore, nor since Thou hast spoken unto Thy servant; for I am slow of speech, and of a slow tongue.’