I have a dream that one day every valley shall be exalted .every hill and mountain shall be made low , the rough places will be made plains , and the crooked places will be made straight , and the glory of the Lord shall be revealed , and all flesh shall see it together.
Could someone help me in understanding why did the speaker not use "shall be" instead of "will be" in the bold area; although, in all lines he used "shall be" even when "will be" should be used.