大方廣佛華嚴經隨疏演義鈔 84.47

84.47

疏「生而室空」者，相師占云是善相，故亦云善吉，亦云空生，其義一耳。解空第一，得無諍三昧，有供養者現與其福，故云善吉。

Regarding the Commentary's phrase 'born when the room was empty': the physiognomist divined that this was an auspicious omen, so he was also named 'Good Fortune' (Subhūti) and also 'Born of Emptiness'; the meanings are identical. Foremost in understanding emptiness, he attained the samādhi of non-dispute; when someone made offerings to him, he would immediately bestow blessings upon them, hence he was called 'Good Fortune'.