בָּח֛וֹן נְתַתִּ֥יךָ בְעַמִּ֖י מִבְצָ֑ר וְתֵדַ֕ע וּבָחַנְתָּ֖ אֶת־דַּרְכָּֽם׃
我已使你在我百姓中作堅固的高臺、作堡壘，好使你知道並察驗他們的行徑。
Rashi
I have made you the strong one This was said to Jeremiah. I have made you the strong one in their midst, and you shall know and test their way, that he tested them and they will not heed. בחון is an expression of strength. Comp. (Isa. 32:14) “rampart and tower (בחן),” also (ibid. 23:13) “they erected its towers (בחוניו).”