'Verily the Prophet (SAWA) once passed by a pile of wheat, so he placed his hand in and his fingers hit upon some moisture, at which he asked the vendor, 'What is this O vendor of wheat?' to which he replied, 'The rain fell on it O Prophet of Allah.' The Prophet then asked him, 'Then why did you not place it at the top of the pile that people might see it?! He who swindles us is not of us.?