The Greater Holy Assembly (Idra Rabba Qadisha) 36
864“This is that same which is written, Ps. cxlvii. 5: ‘Great is our Lord and great is His power.”
865“And whilst He is mitigated by the disposition of the venerable and holy beard (of Macroprosopus), and this (beard of Microprosopus) reflected that, then through its light is He called ‘God merciful,’ Exod. xxxiv. 6: ‘and gracious, long-suffering, and abundant in goodness and in truth.’ And thus is the second disposition instituted.
866“When He shineth in the light of the Ancient of Days, then is He called ‘abundant in Mercy,’ and when another of the other forms is considered, in that form is He called ‘and in truth,’ for this is the light of His countenance.”