The verse has two parts. The first half continues Yahweh’s promise to his people, while the second half is a concluding affirmation from him.
The least one shall become a clan, and the smallest one a mighty nation: God expands here on the promise of growth from the shoot made in the previous verse. For Good News Translation and Contemporary English Version this promise is about the smallest “family” that becomes a nation. However, for most versions The least one and the smallest one refer to all those who see themselves as unimportant among the people of Judah. The hyperbole here emphasizes the promise to those who are poor and at the bottom of the social scale. Even those who are least important among the people will become a clan. The Hebrew word rendered clan is the numeral “a thousand” (New International Version, Revised English Bible, New Jerusalem Bible, Bible en français courant), which also has the sense of a group or a military unit. So this term implies numerical growth as well as increased power. The Hebrew word rendered the smallest one points to insignificant people. Such people have the possibility of becoming a mighty nation. This latter phrase echoes the promise to Abraham in Gen 18.18. Judah will again become a numerous and powerful nation like that promised to its forefathers.
I am the LORD repeats the statement of divine identity found throughout Second Isaiah (see, for example, 42.6, 8; 45.5; 49.23). It gives authority to the promises here. Good News Translation places this affirmation last to give it extra emphasis.
In its time I will hasten it means God will do what he has promised as quickly as possible. The pronouns its and it refer to his promises in this subsection. In its time refers to God’s appointed time for these promises, which is not far off. Good News Translation expresses this line well, saying “When the right time comes, I will make this happen quickly.”
For the translation of this verse consider the following examples:
• The few will become a thousand,
the least significant will become a powerful nation.
I am Yahweh.
When the time is right, I will act quickly.
• The least one will become a military unit,
the least significant will become a strong nation.
I am Yahweh.
I will fulfill these promises on time and quickly.
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 .

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