Thabit ibn 'Ubayd said, "I came to a group which included 'Abdullah ibn 'Umar who said, 'When you greet, make it clearly audible, for it is a greeting from Allah containing great blessing.:  

أَتَيْتُ مَجْلِسًا فِيهِ عَبْدُ اللهِ بْنُ عُمَرَ، فَقَالَ‏:‏ إِذَا سَلَّمْتَ فَأَسْمِعْ، فَإِنَّهَا تَحِيَّةٌ مِنْ عِنْدِ اللهِ مُبَارَكَةً طَيْبَةً‏.‏