The coming of Elijah
The prophet Elijah figures on Seder night more than does Moses.
There is only one – incidental – mention of Moses in the Haggadah.
The reason why the compilers of the Seder service left Moses out and deliberately downgraded him was to show that the redemption of Egypt was brought about by God, “not a serach, not an angel, not a messenger”.
Like Moses, Elijah does not personally appear in the Haggadah, but over time Jewish life has developed a major link between the Seder and Elijah.
Elijah has become one of the favourite heroes of Judaism.
Tradition says that he will visit each Jewish home on this important evening, partly in order to solve the ancient exegetical problem of whether we should have four or five cups of wine (Exodus 6 has five verbs of redemption; shouldn’t we therefore have five cups?).
More importantly, his arrival will be the advance notice that Mashi’ach is on his way.
As foretold at the end of the Book of Malachi, which is the haftarah for Shabbat HaGadol, Elijah will announce “the coming of the great and awesome day of the Lord”.
Paralleling the Egyptian redemption, the future redemption will come on Pesach.