Netziv:Jews in Egypt did not keep Torah & Mitzvos

Netziv (Bamidbar 15:41): I am the L-rd your G‑d…I am the L‑rd your G‑d. This repetition is explained in Menachos(44a) as G‑d will give punishment in the future and He will give reward in the future. However according to the plain meaning it is describing two types of circumstances for serving G‑d. When the Jews were in Egypt there were some very spiritual people who were attached to G‑d and G‑d in turn watched over them in miraculous fashion according their spiritual level. In contrast the masses prior to being redeemed from Egypt knew nothing about Torah and mitzvos. Consequently they did not have Divine providence (hashgocha protis) as individuals for their deeds until they were actually redeemed from Egypt and accepted the Torah and mitzvos. After they accepted the Torah and mitzvos the nature of providence changed so that it was a direct result of their deeds – but it was concealed. That is why there is a repetition of this phrase. Corresponding to the first “I am the L‑rd your G‑d” it indicates that providence is a reflection of the individual’s deeds since it adds that the Jews were taken out of Egypt. The second time it states “I am the L‑rd your G‑d” without mentioning the redemption from Egypt and thus it refers to the relationship that existed in Egypt itself. Thus we see that hashgocha protis is dependent on observing mitzvos and is different for those on a high spiritual level…. In Egypt the Jews had not accepted the Torah and mitzvos and in fact did not know what they were – except for the greatest of the generation who had received the traditions from the Patriarchs. But in general Torah had been forgotten from the masses and those who wanted to serve G‑d did it according to what made sense or seemed nice. In contrast when they were redeemed from Egypt G‑d gave them all Torah and mitzvos…

[A related idea is found here ]

Chazon Ish (Letters I:208): Responded to the assertion that the Jews in Egypt were on the highest level in Torah, Mitzvos, faith and piety. The assertion was based upon the medrashism which said that the righteous women went to the fields and gave birth and left their children and there were many miracles done for them…The deduction being that surely because of these righteous women and these miracles – the entire Jewish people must of have been totally devoted to G-d and his mitvos. A further foundation of this assertion was the medrash which states that the Jews were only enslaved for 86 years and that this is insufficient time to become significantly dissolute and debased. The Chazon Ish said that these deduction have no basis since they are all against what Chazal themselves say on the subject.   He concludes that the assertion that it was impossible for the Jews to become ruined since they saw miracles is not valid. In fact the Jews saw miracles when they were redeemed from Egypt and at the Sea, as well as the Manna and at the giving of the Torah – and yet they made the Golden Calf. Furthermore there were 10 miracles at the Beis HaMikdash and many miracles and wonders done by the Prophets – nevertheless this did not prevent them from having free will to serve idols. one should not interpret the early generations in such a way that it is impossible for us to comprehend and learn from them. In fact they had free will and this is the main thing in avodas HaShem.