(to do sth. ) plainly, unaffectedly, without excessive pondering, speculation etc
simply and unpretentiously
without unnecessary embellishment
without being (trying to be) too clever about it
without undue theorizing.
(author's usage) «Знаю, что не веруется, - а вы лукаво не мудрствуйте отдайтесь жизни прямо, не рассуждая...» (Достоевский 3). "I know belief (in God) doesn't come easily-but don't be too clever about it, just give yourself directly to life, without reasoning..." (3c).
Words of the chronicler Pimen in Aleksandr Pushkin's tragedy Boris Godunov («Борис Годунов»), 1831.
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.