In Numbers 17 we have God's vindication. Before we consider this matter, I would like to add a word concerning the descendants of Korah.
Numbers 16 seems to indicate that all of Korah's family, including his children, perished. But Numbers 26:11 tells us that the sons of Korah did not die. Either they did not take part in that conspiracy and rebellion, or they took Moses' word in 16:26 and departed from the tent of their father and thereby escaped the tragedy that took place when the earth opened and swallowed Korah and his company.
In 1 Chronicles 6:33-37, a record of the genealogy of Samuel, we are told that Samuel was a descendant of Korah. Korah aspired to have a higher position in the priesthood. He did not attain it and he became rebellious. However, one of his descendants became a priest, not by struggling for power but by being offered as a Nazarite. (See Messages Eight through Ten on being sanctified to be a Nazarite.) Samuel was not only a priest but also a great prophet.
Furthermore, as the title of Psalm 88 indicates, this psalm was written by Heman, a descendant of Korah and a grandson of Samuel (1 Chron. 6:33). Heman was not only a psalmist but also a singer in the temple under David's arrangement.
In God's sparing Korah's descendants, we can see His mercy. One of Korah's descendants became a great prophet and took part in the priesthood. Another became one of the psalmists, a writer of one of the best psalms and a temple singer and musician. Thus, from the history recorded in the Old Testament, we can see that God is severe to some but merciful to others. Whether we experience His mercy or His severity depends on how we behave ourselves.
Numbers 17 is a chapter on God's vindication. God's vindication always goes along with His judgment. Hence, His judgment and His vindication cannot be separated. Actually, God's judgment is a form of vindication. But judgment is mainly on the negative side, and vindication is mainly on the positive side. On the negative side, in chapter sixteen God judged Korah, Dathan, Abiram, and the other rebels, including not only the two hundred fifty leaders of the assembly but also the company of Korah. In carrying out this judgment, God exercised His righteousness. In chapter seventeen God went further to vindicate Aaron and Moses, His deputy authority, in a positive way.