None of you should walk wearing one shoe; either wear both of them or take them both off
Authentic hadithعن أبي هريرة رضي الله عنه عن النبي صلى الله عليه وسلم قال: «لا يمش أحدكم في نعل واحدة، لِيُنْعِلهما جميعًا، أو لِيَخْلَعْهُمَا جميعًا».
Abu Hurayrah (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) said: "None of you should walk wearing just one shoe; either wear both of them or take them both off."
Explanation
In this Hadīth, the Prophet (may Allah's peace and blessings be upon him) prohibits us from walking with one shoe and tells that we should either wear both shoes or take them both off and walk barefooted. This manner shows the precision of the Islamic Shariah and the fact that it encompasses all aspects of life.
Source · Narrated by Bukhari & Muslim
From the Hadith Encyclopedia (hadeethenc.com).