Aba Saeed al-Khudri reported: The Messenger of Allah ﷺ said: water (bath) is necessary only when there is seminal emission. And Abu Salamah followed it.
Related hadith on this topic
Explanation & Benefits
Shaykh Umar Farooq Saeedi
Benefits and Issues:
➊ Some of the Companions (Sahabah) and Followers (Tabi'in) held the opinion that ritual bath (ghusl) does not become obligatory unless ejaculation occurs; however, the majority were of the view, as mentioned above, that this was a concession in the early period of Islam. Later, ritual bath (ghusl) was made obligatory upon the meeting of the two circumcised parts (i.e., penetration), and now this is the correct position. These narrations have been compiled together in Sahih Muslim. [صحيح مسلم حديث : 343 وما بعد]
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 217