The Ruling on Omitting Rinsing the Mouth in Ablution

Question:
The questioner says: I do not rinse my mouth during wudu' (ablution) because of the fear of swallowing water. Is this wudu' permissible? I do not rinse my mouth during wudu' because of the fear of swallowing water?

Answer:
This is from Shaytan, my brother. Rinse your mouth and spit out the water; do not swallow any of it. Rinse your mouth, for the mouth is considered part of the exterior, not part of the interior. It is considered part of the exterior. Rinse your mouth with water and sniff water into your nose, then expel it. This is easy, praise be to Allah. However, if you omit rinsing your mouth, your wudu' is not valid.
Because you have left part of your face unwashed, for the inside of the mouth is part of the face, and the inside of the nose is part of the face. If you omit sniffing water without an excuse, your wudu' is not valid. If you omit rinsing your mouth without an excuse, your wudu' is not valid either. And if you omit it for an excuse, you must perform tayammum (dry ablution) in addition to the wudu'. Yes.