Because of the LORD’s presence in Egypt, he will send someone to save them whenever they are oppressed and they cry to him for help.
It will be a sign and a witness to the LORD of hosts in the land of Egypt: The pronoun It refers to both the altar and the pillar mentioned in the previous verse, so it may be rendered “They” (Good News Translation, New Jewish Publication Society’s Tanakh). A sign is a symbol of something (see 7.11), while a witness testifies to something (see 8.2). Here they symbolize and point to Yahweh’s presence in Egypt. In languages where a witness can only be a living person, this noun may be rendered “reminder.”
When they cry to the LORD because of oppressors he will send them a savior, and will defend and deliver them: This recalls language found often in the book of Judges (see, for example, Jdg 2.16-18; 4.1-24). The pronoun they refers to the people in Egypt, so Good News Translation says “the people there.” New Jewish Publication Society’s Tanakh has “the Egyptians” to avoid any ambiguity (also Bible en français courant, Die Bibel im heutigen Deutsch). The verb cry in this context means to call out for help (so Good News Translation). The noun oppressors can be expressed as a relative clause, for example, “those who oppress them” or “those who attack them.” In the Old Testament savior often refers to any person who rescues or delivers others from an enemy threat. It does not point here to a single, historical person, and does not carry the full New Testament implication of the term. A savior will rescue the Egyptians whenever they are oppressed and call for help. The Hebrew word rendered defend is actually a participle meaning “one who defends.” It qualifies savior by forming a hendiadys with it, so he will send them a savior, and will defend and deliver them may be rendered “he will send them a savior and defender to rescue them.” If the receptor language needs an indirect object for the verb deliver, translators can add “from their enemies.”
Possible translation examples for this verse are:
• They [or, These] will be a sign and a witness to Yahweh of hosts in the land of Egypt. When the people there plead with Yahweh because they are oppressed, he will send a savior and defender to rescue them.
• They will symbolize and witness concerning Yahweh of hosts in the land of Egypt. When the people there are oppressed and they call to Yahweh for help, he will send someone who will save and defend them. That person will deliver them [from their enemies].
Quoted with permission from Ogden, Graham S. and Sterk, Jan. A Handbook on Isaiah. (UBS Helps for Translators). New York: UBS, 2011. For this and other handbooks for translators see here .