"When one is enabled to do perform many acts of worship and obedience such as night prayers, fasting, charitable spending, providing for his family, being generous and abstaining for forbidden matters, he should not be deceived by his good deeds. Despite his many good deeds and many acts of obedience, he should not be deluded by any of that. He should always remain fearful.
This fear – coupled with knowledge and with an abundance of good deeds – is a sign of eman and truthfulness, just as our Lord said while describing the complete believers:
وَالَّذِينَ يُؤْتُونَ مَا آتَوا وَّقُلُوبُهُمْ وَجِلَةٌ أَنَّهُمْ إِلَىٰ رَبِّهِمْ رَاجِعُونَ
Those who give what they give while their hearts are fearful because they will be returning to their Lord. [23:60]......
cont/..
This is like what al-Hasan al-Basri said:
A believer brings together both good deeds and fear, while a munafiq brings together bad deeds and a feeling of security.
A believer does good and fears; he does not do good and become deluded. Rather, he does good and fears, and he remains fearful even while hoping for Allah’s rewards.
-Shaykh Abdur Razzaq al Badr / Explanation of Tafsir Ayaat min al-Qur’an al-Kareem lesson