A man once asked Abû Hurayrah – Allâh be pleased with him, ‘What is al-taqwâ?” He replied, “Have you ever taken a path filled with thorns?” The man replied, “I have.” Abû Hurayrah asked him, “What did you do?” He replied, “When I saw a thorn I would dodge it or pass over it or behind it.” Abû Hurayrah said, “That is al-taqwâ.”
Al-Baihaqî, Al-Zuhd Al-Kabîr p351.
Miftaahul-Ilm - Key to Knowledge 