Can I be excused by God for making a mistake out of ignorance?

The vast majority of Islam’s [Sunni] scholars believe that, if a Muslim commits an action that is contrary to the teachings of Islam out of ignorance, then this ignorance protects him/her from being charged with disbelief. This will also prevent this Muslim from being punished on the Day of Judgment as an unbeliever. They [these scholars] depended on the following evidence [all of which are examples of acts of disbelief that are forgiven] for their ruling.

First: In Chapter 5 of the Qur’an, the Table (al-Ma’ida), there is an account of the mistakes made by Jesus’ disciples. Among these are those who in their ignorance of the character of God the All-Powerful, and their doubt in the truth of the Prophet Jesus (upon him be peace), ask Jesus to prove his God’s power.

God mentions these failings in the following verse: “When the followers of Jesus said: O Jesus, son of Mary! Is thy Lord able to send down for us a table spread with food from heaven?” (Q. 5:112)

Such a question suggests that these followers doubted the omnipotence of God, which, in itself, is an act of disbelief. Yet, due to their ignorance of God’s nature, they were excused their sin.
Second: The sons of Israel implored Moses (upon him be peace):

“O Moses! Make for us a god even as they have gods. He said: Lo! Ye are a folk who know not”. (Q. 7:138)

In fact, here, there is no doubt that the sons of Israel are culpable of a great sin in asking him to make them an idol to worship. Yet, there were not described as unbelievers due to their ignorance, which protected them and provided them with an excuse.

Third: [The hadith collector] Ibn Majah reports that when Mu‘az returned from the Levant, he threw himself to the ground before the Prophet (upon him be peace). When the Prophet recoiled and asked him what he was doing, he replied: “When I was in the Levant, I saw people prostrating before the bishops and elders of the church, so I felt that we should do the same before you”. The Messenger of God (upon him be peace) replied: “Never do so, if I had wanted to prostrate to someone other than God, I would have commanded the woman to prostrate in front of her husband”. (Ibn Majah, 1926)

Prostrating in worship to someone other than God is an act of polytheism. However, the Prophet (upon him be peace) was able to teach him [Mu‘az] that prostration is a form of worship and, thus, that it may not be practiced except when intended solely for God; and he did not charge him of disbelief.

Fourth: Al- Bukhari reported that Ibn 'Umar reached 'Umar ibn al- Khattab in a travelling party, having sworn n oath on the name of his father. The Prophet called out to them, saying: "You must know that God prohibits the taking of oaths. Anyone who takes an oath should swear by God, or remain silent".

Making an oath by anything other than God constitutes an act of polytheism.
This is explicitly confirmed in the hadith: “someone who swears on [a name] other than God is an unbeliever (mushrik)”. However, ‘Umar was unaware of this rule, and thus was excused on the grounds of his ignorance.

These examples [and there are many others] prove that a Muslim who, unknowingly, commits a sin against his faith may not be accused of disbelief.

Rather, he should be informed of his error and, pressured with sufficient evidence, to convince him of the errors of his beliefs. If an act of atheism is accompanied by clear proof of ignorance that the person committing this act is ignorant of its importance, then this person may not be judged an unbeliever, nor will he be punished in the Hereafter for his act.