הֲכַיּוֹצֵ֨ר הַזֶּ֜ה לֹא־אוּכַ֨ל לַעֲשׂ֥וֹת לָכֶ֛ם בֵּ֥ית יִשְׂרָאֵ֖ל נְאֻם־יְהוָ֑ה הִנֵּ֤ה כַחֹ֙מֶר֙ בְּיַ֣ד הַיּוֹצֵ֔ר כֵּן־אַתֶּ֥ם בְּיָדִ֖י בֵּ֥ית יִשְׂרָאֵֽל׃ (ס)
¿No podré yo hacer de vosotros como este alfarero, oh casa de Israel, dice SEÑOR? He aquí que como el barro en la mano del alfarero, así sois vosotros en mi mano, oh casa de Israel.
Rashi
Why do You lead us astray Since You have the power to remove the evil inclination, as it is said (Jer. 18:6): “Like clay in the potter’s hand.” Scripture states elsewhere (Ezekiel 36:26): “And I will remove the heart of stone, etc.”
Rabbeinu Bahya
ויחזק ה' את לב פרעה, “G’d reinforced Pharaoh’s resolution.” It is totally unnatural for a person experiencing the kind of plagues Pharaoh and the Egyptians endured not to suffer a total mental collapse. The Torah had already described how, during the first five plagues, Pharaoh had drawn on his psychological reservoirs of obstinacy to stand fast in face of these plagues. Starting with the sixth plague, pestilence, however, G’d had lent him psychological support as we read for the first time in 9,6. This bears out what the prophet said in Jeremiah 18,6, “O House of Israel, can I not deal with you like this potter?- says the Lord. Just like clay in the hands of the potter so are you in My hands!” The prophet continues: “one moment I may decree that a nation or a kingdom shall be uprooted, etc., but if that nation turns back from wickedness I change My mind, etc.” Similarly, Solomon states (Proverbs 21,1) "Like channeled water is the mind of the king in the G-d’s hand; He directs it to whatever He wishes".
Bartenura
"He is the Maker": As the whole world is in His hand like clay in the hand of the [craftsman]. And what is the reason? Because "He is the Creator" that created the whole world ex nihilo. Therefore He can do with it according to His will.