The title of this great play is actually an allusion to the Book of Exodus from the Bible, which says: "The horse and his rider hath he thrown into the sea." Clearly, the title therefore relates to the death of Maurya's sons and the way that the sea has been the reason for all of their deaths. This allusion also represents the theme of fate or destiny, as Maurya seems fated to lose all her sons to the sea, whatever she tries to do to stop this from happening. This relates to the central character of Maurya and the dignity with which she is bestowed in the face of the incredible suffering she has endured and continues to endure. Consider how she is presented in the final speech she gives in the play:
Michael has a clean burial in the far north, by the grace of Almighty God. Bartley will have a fine coffin our of the white boards, and a deep grave surely. What more can we want than that? No man at all can be living forever, and we must be satisfied.
The title, alluding as it does to a part of the Old Testament which declares God's sovereignty and his control over life, therefore introduces one of the central themes in this play, which is the inescapable nature of fate and destiny. Maurya is the central character who is shown to accept and to submit to this force, even when it robs her of everything she has.