What is the ruling on saying: "By me is the unlawful" (عليّ الحرام) without completing it, then saying: "I seek forgiveness from Allah, the Almighty" (أستغفر الله العظيم) afterwards, with the intention of doing something in the future?

The preponderant opinion regarding the phrase "upon me is the unlawful" is that it depends on the intention of the speaker. If he intended divorce or ẓihār, then what he intended takes effect. If he did not intend anything, then nothing is binding upon him. What he intended, whether divorce or ẓihār, is then contingent upon the action to which he intended to link his statement "upon me is the unlawful," and mere intention suffices.

If the divorce occurs before consummation, it is an irrevocable divorce (bā'in), and there is no way to return to the wife except through a new marriage contract. If it occurs after consummation, you may revoke the divorce and return to your wife before the completion of her iddah, provided that this divorce does not complete the three divorces.

In the event of ẓihār occurring, an expiation for ẓihār becomes obligatory upon him, and he must offer it before cohabiting with his wife.