The principle is older than the statute: nobody should sit as judge in their own cause. Illinois codifies it for criminal cases in 725 ILCS 5/114-5(d).
The threshold requirement
The protection attaches to a motion that meets the statutory threshold — typically a verified motion setting out specific cause. A motion that does not meet the threshold may be disposed of differently, which is why verification and specificity matter so much.
What it does not mean
Filing the motion does not automatically remove the judge. The motion must be heard and decided; the point of the rule is who does the deciding.
The documented example
In this record a verified renewed for-cause motion and a notice setting the matter before the named judge bear the same July 23, 2026 file stamp. See the two stamps.