וְקָרַבְתִּ֣י אֲלֵיכֶם֮ לַמִּשְׁפָּט֒ וְהָיִ֣יתִי ׀ עֵ֣ד מְמַהֵ֗ר בַּֽמְכַשְּׁפִים֙ וּבַמְנָ֣אֲפִ֔ים וּבַנִּשְׁבָּעִ֖ים לַשָּׁ֑קֶר וּבְעֹשְׁקֵ֣י שְׂכַר־שָׂ֠כִיר אַלְמָנָ֨ה וְיָת֤וֹם וּמַטֵּי־גֵר֙ וְלֹ֣א יְרֵא֔וּנִי אָמַ֖ר יְהוָ֥ה צְבָאֽוֹת׃
我必臨近你們，施行審判；我必速速作見證，指證行邪術的、犯姦淫的、起假誓的，以及剋扣雇工工錢、欺壓寡婦孤兒、屈枉寄居者，並且不敬畏我的人。萬軍的永恆者說。
Mesillat Yesharim
In the chapter "All are Liable" (Chagiga 5a): "When Rabbi Yochanan would come to this verse, he would weep - 'I will come near you to judgment and I will be a swift witness...' (Malachi 3:5) - a servant whose minor offenses are weighed just like major offenses, is there any remedy for him?
Mesillat Yesharim
Besides all this, all the free time he has left from his affairs, if he is wise, certainly he should not waste it. But rather to immediately grasp hold of it and not be lax in it, utilizing it to toil in the affairs of his soul and the improvement of his service of G-d.
Mesillat Yesharim
Why is this so? Because just like the essence of "watchfulness" involves putting matters to mind, so the essence of laughter is to remove from one's mind straight, rational thinking so that thoughts of fearing G-d do not enter his heart at all.