115:4 In the morning, we daven early so that we won’t be eating after the time that chometz becomes prohibited. It is proper to divide the meal into two parts by bentching, taking a break to go for a walk or learn some Torah, and then returning to wash and eat again, followed by another bentching. This is done to fulfill the mitzvah of eating three meals on Shabbos. (If there isn’t time to take a break in between meals, then one should not do this because to bentch and then immediately wash again would be making unnecessary brachos. One would then have to make his third meal on meat, fish or fruit without bread – Mishnah Brurah 444:8.)
115:5 The haftarah is read from the third chapter of the Book of Malachi because it’s says there, “Bring all the tithes to the storehouse,” which is relevant because some opinions say that erev Pesach was the time in the fourth and seventh years of the Sabbatical (shemittah) cycle when a person took the tithes he had collected for three years and gave them to a Levite.