﴿ بِسْمِ ٱللَّهِ ٱلرَّحْمَٰنِ ٱلرَّحِيمِ إِذَا جَآءَكَ ٱلْمُنَٰفِقُونَ قَالُوا۟ نَشْهَدُ إِنَّكَ لَرَسُولُ ٱللَّهِ ۗ وَٱللَّهُ يَعْلَمُ إِنَّكَ لَرَسُولُهُۥ وَٱللَّهُ يَشْهَدُ إِنَّ ٱلْمُنَٰفِقِينَ لَكَٰذِبُونَ ﴾

“WHEN THE HYPOCRITES come unto thee, they say, "We bear witness that thou art indeed God's Apostle!" But God knows that thou art truly His Apostle; and He bears witness that the hypocrites are indeed false [in their declaration of faith].”

It is a sign of hypocrisy in an individual if he indulges in tall talk and resorts to swearing oaths to reassure others of the truth of his words. A sincere man is subdued out of fear of God. He speaks more from his heart than from his tongue. A hypocrite is eager for men to hear his voice, while a sincere man is eager for God to hear his voice.