when idh is semantically connected to rahma ‘mercy’ he called out to his Lord a call entailing a supplication in secret in the middle of the night because this time of the night invites a faster response to one’s supplication.
- 19:33
إِذْ نَادَىٰ رَبَّهُ نِدَاءً خَفِيًّا
When he called to his Lord inwardly,
- common.revelation-Meccan
- common.hizb : 122