user11674: In the Sanditthika Sutta,

"The fact that when a delusive quality is present within you, you discern that a delusive quality is present within you; and when a delusive quality is not present within you, you discern that a delusive quality is not present within you"

A similar description is also given in the Satipatthana Sutta. The second part, "to know when something is not present inside of me", is to be understood how? Do I literally acknowledge at any point in my daily life that I have currently no defilements in me? And if the answer is yes, what do I do with that acknowledging?

user8157: The four right efforts in the noble path are: 

effort to prevent unwholesome mental states.
effort to abandon unwholesome mental states.
effort to develop wholesome mental states
effort to maintain & increase wholesome mental states

Therefore, when the mind without delusion is discerned, the effort is made to maintain the mind without delusion, which requires governance or supervision by mindfulness. 

11674: <p>In the <a href="https://www.accesstoinsight.org/tipitaka/an/an06/an06.047.than.html" rel="nofollow noreferrer">Sanditthika Sutta</a>,</p>

<blockquote>
  <p>"The fact that when a delusive quality is present within you, you discern that a delusive quality is present within you; and when a delusive quality is not present within you, you discern that a delusive quality is not present within you"</p>
</blockquote>

<p>A similar description is also given in the Satipatthana Sutta. The second part, "to know when something is not present inside of me", is to be understood how? Do I literally acknowledge at any point in my daily life that I have currently no defilements in me? And if the answer is yes, what do I do with that acknowledging?</p>
 8157: <p>The four right efforts in the noble path are: </p>

<ol>
<li><p>effort to prevent unwholesome mental states.</p></li>
<li><p>effort to abandon unwholesome mental states.</p></li>
<li><p>effort to develop wholesome mental states</p></li>
<li><p>effort to maintain &amp; increase wholesome mental states</p></li>
</ol>

<p>Therefore, when the mind without delusion is discerned, the effort is made to maintain the mind without delusion, which requires governance or supervision by mindfulness. </p>
