In Matthew 5:29 and Isaiah 3:8, this signifies to change truth into falsities, and to fall thereby.

In Isaiah 8:14, this refers to people who should teach truths from the Word but instead teach falsities. (Apocalypse Explained 624)

To 'stumble' denotes being scandalized or offended, and falling, as a result, from truths into falsities.

(Referencias: Arcana Coelestia 9163)