כל מדותיו של הקב”ה מדה כנגד מדה
“…all the measures of The Blessed Holy One are ‘measure for measure’…” 
In a previous post , I pointed out that the Talmud offers a teaching very parallel to what we learn of “karma” in Yoga, Buddhism and other traditions.
It’s essential expression in Talmud is: מדה כנגד מדה – “measure for measure.” Countless subsequent writings refer to it. (Seeing how this principle is cited in the annual cycle of parshiyot, holidays, etc. would make an excellent course — especially for adults.) Accept it or not, it’s a fundamental idea in Judaism.
The Talmud is explicit: All that happens is fair and just. It might not seem that way to us, but that’s how the rabbis say we should view events that happen to us and around us.
Of course, nowhere do the rabbis teach that when we see someone suffering, we should simply say, with emotional distance, “It must be because of something you did.” Much the opposite — relieving suffering has a place in Judaism second only to not causing suffering in the first place! 
Extending this compassion to innocent victims needs no explanation or defense. But the rabbis even ask why the Egyptians, pursuing the Israelites as they escaped, were drowned. Couldn’t G-d have simply closed up the waves of the Red (or Reed) Sea before Pharaoh got there, blocking him and his army from pursuing and harrassing the B’nai Yisrael any further? Looking into Torah, the rabbis find the answer in the behavior of the Egyptians themselves (especially Pharaoh): 
In Torah, it says, “[Pharaoh said] Come, let’s deal craftily with him…” 
The plain meaning of the text is, “Let’s deal craftily with Israel/the Israelites.” But –
Rabbi Hama ben Hanina said: [by 'him,' Pharaoh meant G-d:] ‘Come; let’s outwit [G-d].’ [i.e. We can destroy Israel by drowing their first born sons, and still avoid the "karmic" consequences.]
…Let’s afflict [Israel] with water , because [G-d] has already sworn that He won’t bring a flood upon the world [i.e. G-d won't drown us in return]; as it is said: ‘For this is like the waters of Noah to Me’… 
[Pharaoh and the Egyptians] were unaware, however, that [G-d] wouldn’t bring a flood upon the whole world, but would bring it upon one people; or alternately, He wouldn’t bring it but they’d go and fall into it [i.e. G-d wouldn't bring the flood down on them, but they'd end up in it anyway, as if 'by accident' -- but really by Divine Design] Thus it says: ‘And the Egyptians fled towards it…’ 
…Rabbi Eleazar said: …They were cooked in the pot they were cooking in…” [i.e. "midah k'neged midah;" their own actions led to their own drowning.]
Thus, Rabbi Hama is saying that Pharaoh and the Egyptian army — all male, of course — were drowned, because at Pharaoh’s command, the male newborns of the Israelites had been drowned.
Still, why were the Egyptian soldiers drowned with Pharaoh? Why not Pharaoh alone? Weren’t they “just following orders?”
In 3 earlier posts, I explored the theme of “Pharaoh” as an abuser — a “bully.”  This topic — bullying — discussed so much today, is far from a new or recent problem.
The soldiers enforced Pharaoh’s commands. In the “bully/bullied/bystander” scenario, they were “bystanders;” they didn’t make the decisions themselves. But – they didn’t oppose them, either. Morally, they were participants.
“[Bystanders]…aid and abet the bully through acts of commission or omission.” 
They must be held accountable, for the sake of society itself:
“Injustice overlooked or ignored becomes a contagion that infects even those who thought they could turn away. The self-confidence and self-respect of the bystanders are eroded as they wrestle with their fears about getting involved and with the knowledge that to do nothing is to abdicate their moral responsibility to their peer who is their target.” 
So, this narrative in the haggadah is a reminder that the consequences of our actions are inescapable, even if we’ve been “bystanders,” and that in the end, this rule always functions for our own good and for the good of the world.
Yet, as I said above — it doesn’t always seem that way to us. In the end, I don’t think the rabbis necessarily meant for us to believe this based on appearances alone. It’s a matter of “faith” which, if accepted, can help reveal G-d’s Presence to us, bring us some peace of mind, and aid us in making behavioral choices with greater consideration for our own well-being, for that of the environment in which we live, and for the world we’ll be leaving to our children.