He or she doesn't even have to make an effort, but remembers his or her fears and re-enacts them. The same goes for the liberated mind-states. Every moment of concentration during meditation is a moment of no defilements, no sorrow and no fear. That sort of experience must be duplicated over and over again. Thereby we reinforce our liberated mind-states and as we remember them we can retain them and act in accordance with them even under ordinary or trying circumstances.
Sensual desire means wanting, renunciation means giving up.
When one gives, one isn't desiring, unless one is wishing for applause or gratitude. If one gives for giving's sake, then there is a moment of no defilement. The same holds true for loving-kindness, compassion and helpfulness, which are all opposed to greed. No worries, no restlessness also add to our freedom. We all know moments without all this dukkha .