* Kennings are poetic phrases that substitute for a single word. They are common in Old English poetry.
* Line 306 of Beowulf is "Hwearf þa on healle, þær him hæl was" (He then turned in the hall, where he was whole/healthy).
Analysis:
* There are no poetic phrases substituting for a single word in this line.
* "Healle" (hall) and "hæl" (health/whole) are straightforward words.
Conclusion:
The statement is false. The Beowulf poet does not use kennings in line 306.