“The Messenger of Allah, may Allah’s peace and blessings be upon him, used to kiss while he was fasting, and he would engage in physical intimacy while he was fasting; however, he had the greatest control among you over his desires.”

Narrated by al-Bukhārī (no. 1927) and Muslim (no. 1106), the wording is his, from the ḥadīth of ʿĀʾishah (may Allah be pleased with her).

Brief Explanation of the Hadith

 Since fasting is a tremendous act of worship, the Prophet (may Allah’s peace and blessings be upon him) was keen to teach his Companions what pertains to this noble act of devotion, clarifying what is permissible therein and what is not, both through his statements and his actions. Among that is the clarification of matters related to marital relations during fasting.
Thus, on the authority the Mother of the Believers, ʿĀ’ishah (may Allah be pleased with her), who said: “The Messenger of Allah (may Allah’s peace and blessings be upon him) used to kiss while he was fasting, and he would engage in intimate contact while he was fasting.” That is, he would kiss his wives and engage in physical intimacy short of intercourse while observing the fast, whether the fast was obligatory or voluntary. This indicates that fasting does not preclude kissing or such intimate contact, even though the latter is more stimulating to desire than kissing. However, she (may Allah be pleased with her) pointed out a matter of utmost importance: that kissing and intimate contact are among the causes that can invalidate the fast, and a person may not have control over himself during intercourse. She said: “However, he had the greatest self-control among you over his desires.” It is said: irbihi and arabihi. Irb (with kasrah) refers to the organ, while arab (with a fatha on the alif and raa’) refers to desire or the need of the self. The meaning is the same: that he (may Allah’s peace and blessings be upon him) had the greatest ability among you to control himself and mastery over his desires. His inclinations were subject to his command and did not lead him to anything that would invalidate his fast.
The ḥadīth indicates that there is no exclusivity in this matter for the Prophet (may Allah’s peace and blessings be upon him); rather, it is a general legislation for his nation, provided that a person can safeguard his fast from invalidation. If he fears that it may lead him to intercourse or ejaculation, then it is prohibited for him, for means are governed by the rulings of their intended ends, especially in the fast of Ramadān.
Among the benefits of this ḥadīth are: the exemplary conduct of the Prophet (may Allah’s peace and blessings be upon him) with his wives; the permissibility of generally describing what occurs between spouses when necessary; the fact that this is a legislation for the nation; and it also demonstrates the virtue and knowledge of ʿĀ’ishah (may Allah be pleased with her).