Kommentar zu Schemot 14:24

באשמרת הבקר IN THE MORNING WATCH — The three divisions of the night are each called an אשמורה “a watch” (Berakhot 3b), and that which immediately precedes the morning is called “the morning watch”. I am of opinion that because the night is divided for the watches (משמרות) of the song of the ministering angels — company after company — into three divisions, therefore each division of the night is termed, for all purposes, an אשמרת (another form of משמר the angel’s watch), and this is what Onkelos has in mind when he translates אשמרת by מטרת.

וישקף ה' אל מחנה מצרים בעמוד אש וענן, the two pillars which were moving halfway between the Egyptians and the Israelites, He now brought much closer to the Egyptian camp.

ויהי באשמרת הבקר, It happened during the morning watch, etc. We need to know why G'd chose to perform this act of retribution in the morning and not during the night which is traditionally the time for the attribute of Justice to be active. I have seen in Yalkut Shimoni item 235 that this is exactly what the angel Gabriel argued before G'd. G'd answered him that he should wait until the hour during which the patriarch Abraham started out on the way to offer his son Isaac as an offering to G'd (we read in Genesis 22,3 that this occurred early in the morning). In other words, although the morning is not the time to exact vengeance G'd reversed His usual procedure for the sake of Abraham's descendants just as Abraham at the time had reversed his natural feelings of love and mercy towards his son in favour of obedience to G'd's request. Israel benefited in that G'd performed the miracle personally, to match the fact that Abraham had personally saddled his donkey at the time though he had hundreds of servants at his disposal to perform that task for him. The Torah writes: "G'd looked down on the camp of Egypt; this means that He Himself went into action. The fact that the Egyptians drowned in daylight enabled the Israelites to witness the death of their enemies.