Say, "If the sea were ink for [writing] the words of my Lord, the sea would be exhausted before the words of my Lord were exhausted, even if We brought the like of it as a supplement"(18:109). The City of knowledge is the Prophet (sAs) and its gate is S. Ali Ibn Abi Talib . Prophet's order is to seek knowledge even if it is in China and Allah commands, "Wa Dhakkir" (Remind)...