How to reconcile the prohibition against saying "if" with the hadith: "If I had known what I know now, I would have..."?

Question:
This is a question about the prohibition of saying "if," as in "if I had done such and such, then such and such would have happened."

Answer:
If you open the door to the work of Satan, and between the saying of the Messenger (peace and blessings be upon him) . The first one contains blame regarding the divine decree, distress over what happened, and self-reproach. As for the saying of the Messenger , this contains regret over an action, regret over a righteous deed. Regret over a righteous deed is not blame regarding the divine decree; rather, it is regret over what was missed of tamattu', which is better than qiran. "If I had known in advance what I know now, I would not have brought the sacrificial animals, nor would I have exited the state of ihram with you." This is regret over the loss of additional reward, and regret over a righteous deed. And this is a good thing. It does not fall under blaming the divine decree.