Letters 95.38

It will therefore be of no avail to give precepts unless you first remove the conditions that are likely to stand in the way of precepts; it will do no more good than to place weapons by your side and bring yourself near the foe without having your hands free to use those weapons. The soul, in order to deal with the precepts which we offer, must first be set free.

Seneca, Letters to Lucilius 95.38, translated by Richard Mott Gummere