Anottappīsutta

sn16.2:2.1 To what extent is this the case?”

sn16.2:2.3 “Reverend, take a mendicant who doesn’t foster keenness by thinking: ‘If unarisen unskillful qualities arise in me, they’ll lead to harm.’ ‘If I don’t give up arisen unskillful qualities, they’ll lead to harm.’ ‘If I don’t give rise to unarisen skillful qualities, they’ll lead to harm.’ ‘If arisen skillful qualities cease in me, they’ll lead to harm.’

sn16.2:2.4 That’s how you’re not keen.