What are "Ya'aros ha'Devash "?
Rashi citing R. Nasan ha'Yishmaeli: They were sugar canes. This is like "va'Tasem ba'Suf" (Shemos 2:3); the Targum is "va'Shavisah b'Ya'ara." "Suf" are swamp reeds. The same applies to "Achalti Yari Im Divshi" (Shir ha'Shirim 5:1).
Radak: They are loaves of honey, like from which they extract honey. This is like "Achalti Yari Im Divshi" (Shir ha'Shirim 5:1). Yonason translates 'b'Kina d'Duvsha', because the loaf is made of many cells.
Why does it mention that he dipped the end of his stick in the Devash?
Malbim: There were three defenses of Yonason. (a) He had not heard - he was Shogeg. (b) He ate only a little from the end of his stick - it is a Safek if the decree forbade this! (c) His eyes had darkened due to Bulmus 1 (a dangerous level of) hunger. In such a state, he was proper to eat according to letter of the law.
Yuma 83b says that on Yom Kipur, we feed even honey to one who seized by Bulmus. It says that we cannot bring a proof from Yonason, for that was not Bulmus! Perhaps Malbim explains that it is a mere Dichuy; one could say that perhaps he was not seized by Bulmus. (PF) Torah ha'Temimah - the Gemara infers that it was not Bulmus, for then Yonason would be permitted even if he knew about the Shevu'ah!
Why is it written va'Tir'enah, and we pronounce it va'Ta'ornah?
Radak: The pronunciation shows that his eyes were dark and weak from hunger and fatigue [and they enlightened]. The writing is from the root to see; they refer to the same matter.
