What is the excuse of ignorance, and does it apply to someone who lives in a non-observant Muslim environment and fears committing errors in acts of worship and beliefs due to their ignorance?

It is recommended to continue studying Islamic knowledge, to educate family and society, and to frequently recite the reported supplication: "O Allah, I seek refuge in You from associating partners with You knowingly, and I seek Your forgiveness for what I do not know." One should begin gradually by reading books on sound doctrine (aqidah) and jurisprudence (fiqh).

The possibility of errors in doctrine and worship should be dismissed to avoid obsessive doubts (waswasa). If an error is discovered in prayer, there is no need to repeat previous prayers; rather, only the current prayer should be rectified, as maintained by Sheikh al-Islam Ibn Taymiyyah, who argued that the Prophet, peace and blessings be upon him, commanded the one who prayed incorrectly to repeat the prayer of that time and did not command him to repeat past prayers.

If a person falls into a doctrinal error, he is not considered an apostate (kafir) by it until proof is established against him, for Allah has forgiven this nation for its errors. The early generations (Salaf) might have disagreed on issues without declaring anyone an apostate or a transgressor (fasiq), because a statement might be disbelief (kufr), but it might be hidden from some people that it is disbelief, so a specific person is not declared an apostate until proof is established against him.