Verse 41

कदाचिदान्तरान् स्पर्शान्परित्यज्य मनःकपिः ।लोलत्वात्तस्य संयातो विषयं विषदग्धवत्

In plain words

Sometimes the monkey of his manas, having abandoned the inner contacts, went off through its fickleness to a sense-object, like one burned by poison.