It has been narrated on the authority of Jarir b. Abdullah who said:I saw that the Messenger of Allah (ﷺ) was twisting the forelock of a horse with his fingers and he was saying: (A great) benefit. i. e. reward (for rearing them for Jihad) and spoils of war, has been tied to the forelocks of horses until the Day of Judgment

The above tradition has also been narrated on the authority of Yunus through a different chain of transmitters