Shara'i` is the plural of Shari`ah Shari`ah is in the sense of Mashru`ah, that is the Divine injunctions. These Divine injunctions are of various kinds, i.e., some of them are obligatory, some desirable and some voluntary. The obligatory ones are compulsory and their compliance is indispensable. What is termed as Mustahabbat (desirables) are also highly important for gaining the Pleasure of Allah. Similarly, voluntary acts are a means of getting close to Allah. Ordinary people are sometimes puzzled by the abundance of the latter and want to adhere to the first two, that is obligations and what comes in the category of desirables. A desire to this effect is mentioned in this Hadith. The Prophet (PBUH) answered the query in this matter by saying to the inquirer, "Keep your tongue wet with the remembrance of Allah." Keeping the tongue wet with the remembrance of Allah here means its abundant recitation. In other words, one should make the remembrance of Allah a permanent feature. If one is not able to do many voulntary good works, which some people find difficult, the remembrance of Allah will make up the deficiency in that regard.