בָּנַ֕י עַתָּ֖ה אַל־תִּשָּׁל֑וּ כִּֽי־בָכֶ֞ם בָּחַ֣ר יְהוָ֗ה לַעֲמֹ֤ד לְפָנָיו֙ לְשָׁ֣רְת֔וֹ וְלִהְי֥וֹת ל֖וֹ מְשָׁרְתִ֥ים וּמַקְטִרִֽים׃ (ס)
My sons, be not now negligent; for the LORD hath chosen you to stand before Him, to minister unto Him, and that ye should be His ministers, and offer unto Him.’
Rashi on II Chronicles
do not forget - Heb. תִּשָּׁלוּ, an expression denoting lack of intention.