Here’s how Spurgeon described this leadership principle:

…it is always best not to know, nor to wish to know, what is being said about you, either by friends or foes. Those who praise are probably as much mistaken as those who abuse us, and the one may be regarded as a set off to the other, if indeed it be worth while taking any account at all of man’s judgement. If we have the approbation of our God, certified by a placid conscience, we can afford to be indifferent to the opinions of our fellow-men, whether they commend or condemn. If we cannot reach this point we are babes and not men.

[Renounce] the love of self. Judge it to be a small matter what men think or say of you, and care only for their treatment of your Lord.