Rashi #1, Ramban and R. Bachye #1: With reference to the various decrees and exiles that Hahem placed (?she?Sam Keil?) beginning with Ashur, Bil'am is woefully exclaiming "Who can survive the decree of Ashur" ¹ - who mixed-up all the nations? Followed by ships from Kitim - alias Rome, who will exile Ashur, and who will themselves ultimately be destroyed. ²

Rashi #2 (on Sanhedrin, 106a): It refers to when Hakadosh-Baruch-Hu redeems Himself from Galus and rewards the Tzadikim when the time comes.

R. Bachye #2 (citing Pirkei d?R. Eliezer: ?Woe to the one who lives in the time of Yishmael!? - the only nation that contains the Name ?Keil? ³ - like Yisrael - who are called Kayin because they lived in the territory of Kayin. ⁴

R. Bachye #3: ?mi?Sumo Keil? hints at ?Sama?el? - Yisrael?s prosecutor on earth, hinted at- Yisrael?s prosecutor in Heaven, in an attempt to gain his support to curse Yisrael. ⁵

Seforno (based on Sanhedrin, 98b): With reference to the terrible afflictions that will accompany the coming of Mashi'ach, it means 'Let him come, but let me not see him!'

Rashbam: With reference to Pasuk 17, it refers to the coming of Mashi'ach, when Hashem carries out His word and he destroys (or subjugates) all the B'nei Sheis.

Targum Onkelos: 'Woe to the Resha'im when Hashem does these things!'

Targum Yonasan: 'Woe to whoever is around when Hashem comes to pay the Tzadikim their just reward and to punish the Resha'im; To break up nations and their kings and to incite one against the other!'

Da'as Zekenim and Hadar Zekenim #1 (in Pasuk 22): It means 'Who can live through what Hashem will place ("mi'Sumo Keil") in the world (Mashi'ach)?!

Hadar Zekenim #2 (in Pasuk 24): After seeing that all the nations will be finished in the days of Mashi'ach, Bil'am lamented 'who will live?'?

Sanhedrin 106a #1 (according to Reish Lakish): 'Woe to the one who tries to keep himself alive through Shum Eil' (by making himself a god). ⁶

Sanhedrin 106a #2 (according to R. Yochanan): 'Woe to the nation that will be subjugating Yisrael when Hashem decides to redeem them. Who will place a coat between a lion and a lioness when they are mating'?

Oznayim la'Torah: 'Who can endure all the troubles that Hashem will place ("mi'Sumo Keil") in the world - the suffering caused by Sancheriv when he destroys nations and mixes up the world, and followed by Edom - alias Rome' (in Pasuk 24).