ثُمَّ دَنَا فَتَدَلَّىٰ
Summa danaa fatadalla
and then approached––coming down
Then he drew near and came down,
The subject of these two verbs is the oldest question in the surah: early readers took the one who drew near to be Jibril, the mighty figure named a few lines above, while others read the approach as God's own. Tadalla describes a bucket let down into a well or a branch bent low with fruit, a downward reaching rather than a step. The second verb deepens the first.