He was asked:

About someone who holds that vomiting invalidates ablution and cites as evidence the report that the Prophet “once vomited and performed ablution.” He also relates another hadith: “He once vomited, washed his mouth, and said, ‘This is how ablution is performed after vomiting.’” Should one act upon the first hadith or the second?

He answered:

As for the second hadith, I have never heard of it. The first is in the Sunan collections, but its wording is:

“He vomited and broke his fast. This was mentioned to Thawbān, who said, ‘He spoke the truth; I poured out the water for his ablution.’”

Whenever the term “ablution” occurs in the Prophet’s speech, it means the ritual ablution prescribed by Islamic law. Its use to mean washing the hands and mouth occurs only in Jewish usage. It has been related that Salmān al-Fārisī said to the Prophet:

“We find in the Torah that ablution before a meal brings blessing to the food.” He replied, “Ablution before a meal and ablution after it bring blessing to the food.”

And Allah knows best.