Assault

Whoever commits an assault upon another shall be punished. In order to prove assault, the Commonwealth must prove beyond a reasonable doubt that a defendant assaulted a person. An assault may be committed in one of two ways.

An attempt or offer to do bodily injury to another by force and violence.
In this type of assault, the Commonwealth must prove beyond a reasonable doubt that a defendant intended to physically harm the victim. Intent refers to a person's objectives or purposes. Finally, the Commonwealth must prove a defendant had the actual ability or apparent ability to inflict bodily harm.

Putting a person in fear of immediate bodily injury

This second type of assault occurs when a defendant, with the intent to cause apprehension of immediate bodily harm, does some act that causes such apprehension.

First, that a defendant possessed the intention to cause apprehension of immediate bodily harm.
Intent refers to a person's objectives or purpose, meaning that the defendant must have had it in their mind to do the proscribed act. It involves concentrating or focusing the mind for some perceptible period. It is a conscious act, with the determination of the mind to do an act. It is contemplation rather than reflex, and it must precede the act.
Reasonable Apprehension
Second, the Commonwealth must show that the defendant engaged in conduct of the sort that would raise a reasonable apprehension of bodily harm. For example, pointing an unloaded gun at a person may constitute assault. However, where the defendant utters threatening words to a person, unaccompanied by any act, such conduct generally is not sufficient to constitute assault.
Reasonable Fear of Harm
Third, the Commonwealth must demonstrate that as a result of the threatened conduct the victim did in fact experience a reasonable fear of immediate physical harm.