The Stumbling Fool
That’s what Mishlei warns us about: חַּ ̃ƒי ב≈ל םַכֲח ֹ̇וו¿ˆƒמ – The one with a wise heart grabs mitzvos, ט≈בַל¿י םƒיַ ָ̇פ¿ׂ ̆ ילƒו¡‡∆ו– while ‘the fool of lips’ will stumble (10:8). It means that the wise person gets busy with achieving while the fool, he’s spouting ideas and ideals but he stumbles into failure.
Now, you have to understand that when Mishlei here is describing the ‘fool of lips’ he’s talking about a person who is not such a big fool because actually it’s a person who is making use of his lips. He is speaking about ideals, about great dreams that he hopes to accomplish—achievements in excellence of character, in finding favor in the eyes of Hashem, in perfection of service of Hashem. He speaks about all that, but ט≈בַל¿י– he stumbles. He is nichshal because it never goes beyond talking. He's םƒיַ ָ̇פ¿ׂ ̆ ילƒו¡‡∆ו – he's a fool because he only talks about these things.
Of course we welcome such fools who talk about great ideals—at least he knows it’s important—but it's a pity on him because he never gets beyond his lips.