What is the ruling on swearing that something is going to happen without making a vow? For example, if one says, "By Allaah, this team will lose the match," and then it wins. Please advise.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

If someone swears an oath that something possible will happen in the future, believing that it will surely happen, and then he turns out to be wrong and that thing does not happen, most of the Muslim scholars believed that the oath-taker, in this case, should pay the expiation for breaking an oath. Some scholars, like Shaykh Al-Islam Ibn Taymiyyah chose another opinion; that the person in this case is not obliged to pay the expiation for breaking an oath. Ar-Ruhaybaani said in his book Mataalib Uli An-Nuha, "Shaykh Taqiyy Ad-Deen (Ibn Taymiyyah) said that if a person swears an oath that something that will happen in the future, believing that it will happen, for sure, and then he turns out to be wrong and it does not happen, his oath is not considered binding. The same applies to taking an oath that someone will do such-and such-thing, believing that he will obey him and fulfill the oath. If this person, about whom that oath has been taken, does not obey the person who swears the oath, no expiation is due in both cases because such an oath is considered a meaningless oath. Allaah The Exalted Says (what means): {Allaah Will not Impose blame upon you for what is meaningless in your oaths, but He Will Impose blame upon you for [breaking] what you intended of oaths.} [Quran 5:89] The Hanbali school of Fiqh adopts a different opinion in this regard."

Anyway, offering the expiation is more prudent, safer in terms of clearing liability, and more likely to insure avoidance of the difference of opinion among scholars. We would like to point out some issues:

1)    Muslims should guard against (unnecessary) swearing to the best of their abilities.  Allaah The Exalted Says (what means): {…But guard your oaths…} [Quran 5:89]

2)    Muslims should preoccupy themselves with what benefits them regarding their religion and worldly affairs and should keep away from what does not benefit them.

 Allaah Knows best.