THE SLOTHFUL DO NOT REALISE THE PATH
Utthana kalamhi anutthahano yuva bali alasiyam upeto
Samsanna sankappamano kusito pannaya maggam alaso na vindati.
Who strives not when he should strive, who, though young and strong, is given to idleness,
who is loose in his purpose and thoughts, and who is lazy - that idler never finds the way to wisdom. 
Once a group of young men were admitted into the Order by the Buddha in Savatthi. After receiving a subject of meditation from the Buddha, all the new bhikkhus, except one, went to the forest to practise meditation. They practised zealously and vigilantly and in due course all of them attained Arahanthood. Then they returned to the monastery to pay homage to the Enlightened One. Bhikkhu Tissa who had stayed behind did not try hard and therefore achieved nothing.
When Tissa found that the other bhikkhus were so much superior to him, he regretted that he had wasted his time. So he resolved to practise meditation throughout the night. As he was walking in meditation that night, he slipped and broke a thigh bone. Other bhikkhus, hearing his cry went to help him. On hearing about the above incident the Buddha said, 'Bhikkhus, one who does not strive when he should be striving but idles away his time will not attain mental absorption (jhana) and purity.'