What is the ruling on the repentance of one who presumes to act as a god over Allah, and is the repentance of one who says with his tongue, "Who is it that presumes to act as a god over me?" accepted?

"Taking liberties with God" (at-ta'alli 'ala Allah) is forbidden. An example of this is found in the Qudsi Hadith, where Allah Almighty says: "Who is he that takes liberties with Me, claiming that I will not forgive so-and-so?! Indeed, I have forgiven so-and-so and have nullified your deed." What you experienced was merely a thought (hadith nafs), and Allah Almighty has forgiven the امت for what they thought to themselves, as long as they did not act upon it or speak about it. Even if you did speak, it was merely an utterance and not an act of "taking liberties with God." Your mention of understanding the meanings of the Quran, focusing in prayer, and weeping out of fear of Allah after this incident is considered a good and accepted repentance, Allah willing. For perhaps a sin can be transformed into a blessing through repentance and brokenness.