When you consider when the Scottish play, also know as Macbeth, the significance becomes very evident. King James had a profound interest in witchcraft and the divine right of kings to rule and thus it is significant.
Furthermore, James' personal connection to the character in Shakespeare's play adds another layer of symbolism and relevance. The witches prophecies in particular resonated with Jacobean audiencies: "All hail, Macbeth, Thane of Cawdor!", "All hail, Macbeth, that shall be King hereafter! " All hail, Macbeth and Banquo!" all resonated. These titles referred not only to Macbeth's own rise to power, but also echoed James own ascent to throne of Scotland in 1567 after the mysterious death of Lord Darnley who was also related to him