Say 'I believe in Allah' and then be Steadfast
On the authority of Sufyan bin Abdullah (may Allah be pleased with him) who said:
"I said, 'O Messenger of Allah, tell me something about Islam which I can ask of no one but you.' He (peace be upon him) said, 'Say "I believe in Allah" — and then be steadfast.'"
عَنْ أَبِي عَمْرٍو وَقِيلَ: أَبِي عَمْرَةَ سُفْيَانَ بْنِ عَبْدِ اللَّهِ رَضِيَ اللهُ عَنْهُ قَالَ:
"قُلْت: يَا رَسُولَ اللَّهِ! قُلْ لِي فِي الْإِسْلَامِ قَوْلًا لَا أَسْأَلُ عَنْهُ أَحَدًا غَيْرَك؛ قَالَ: قُلْ: آمَنْت بِاَللَّهِ ثُمَّ اسْتَقِمْ"
Keeping an upright and steadfast life is following the injunctions that have come from Allah, and leaving that which Allah has forbade.
This hadith emphasizes the importance of proclaiming and saying with the tongue words of belief, as well as living by those words by acting in a manner that affirms one’s proclamation of faith in Allah
This Hadith is an example of the miracle of the Prophet’s comprehensiveness in speech (Jawami’ al-Kalam), as the Prophet(s) has combined for the questioner, in these two phrases “Say: I believe in Allah” and “then be steadfast”, the complete essence of one’s declaration of belief and application of Islam in one’s life through perseverance. These words instruct one to review one’s iman (faith) through the tongue and remembrance of the heart, and they instruct one to remain steadfast (to have istiqamah) upon performing the actions of obedience, and refraining completely from actions of disobedience.
Belief and Action
The Prophet(s) instructs the man “Say: I believe in Allah, then be steadfast” as there is some value in him outwardly stating and restating his belief in Allah. It’s not enough to just say, but to actually follow through with action. Many times, we are very good at talking, but very weak at doing, practicing, and living by our words. Simply saying by the tongue does not absolve us of our responsibility of living by the words we say/proclaim (say or proclaim). The following verse in the Qur’an emphasizes this point:
إِنَّ ٱلَّذِينَ قَالُوا۟ رَبُّنَا ٱللَّهُ ثُمَّ ٱسْتَقَٰمُوا۟ تَتَنَزَّلُ عَلَيْهِمُ ٱلْمَلَٰٓئِكَةُ أَلَّا تَخَافُوا۟ وَلَا تَحْزَنُوا۟ وَأَبْشِرُوا۟ بِٱلْجَنَّةِ ٱلَّتِى كُنتُمْ تُوعَدُونَ
“Indeed, those who have said, ‘Our Lord is Allah’ and then remained on a right course - the angels will descend upon them, [saying], ‘Do not fear and do not grieve but receive good tidings of Paradise, which you were promised.’” (Qur’an, Surah Fussilat, 41:30)
Umar bin al-Khattab (may Allah be pleased with him) said, “They are steadfast upon the obedience of Allah, and they do not swerve away from that with the evasions of the fox.” This means they are firm upon what Allah has ordered from matters of belief, speech, and action. In addition, they consistently persist upon these orders of Allah.
إِنَّ ٱلَّذِينَ قَالُوا۟ رَبُّنَا ٱللَّهُ ثُمَّ ٱسْتَقَٰمُوا۟ فَلَا خَوْفٌ عَلَيْهِمْ وَلَا هُمْ يَحْزَنُونَ
“Indeed, those who have said, ‘Our Lord is Allah’, and then remained on a right course - there will be no fear concerning them, nor will they grieve.” (Qur’an, Surah al-Ahqaf, 46:13)
Relationship Between Istiqamah (Steadfastness) and Istighfaar (Seeking Forgiveness)
قُلْ إِنَّمَآ أَنَا۠ بَشَرٌ مِّثْلُكُمْ يُوحَىٰٓ إِلَىَّ أَنَّمَآ إِلَٰهُكُمْ إِلَٰهٌ وَٰحِدٌ فَٱسْتَقِيمُوٓا۟ إِلَيْهِ وَٱسْتَغْفِرُوهُ ۗ وَوَيْلٌ لِّلْمُشْرِكِينَ
“Say, O [Muhammad], ‘I am only a man like you to whom it has been revealed that your god is but one God; so take a straight course to Him (be steadfast) and seek His forgiveness.’ And woe to those who associate others with Allah.” (Qur’an, Surah Fussilat, 41:6)
The verse informs us we are going to try to be steadfast, but at times we may encounter shortcomings. So, Istighfar (seeking forgiveness) is essential in the process of steadfastness and fulfilling our proclamation of faith.
Anas bin Malik reports the Prophet (sas) said: “The belief of a servant will not be steadfast until his heart becomes steadfast, and his heart will not become steadfast until his tongue becomes steadfast”. (Imam Ahmad)
Having Istiqamah May Require Opposing Societal Norms & Culture
Having Istiqamah, steadfastness in obeying Allah, may require one to differentiate and not practice the incorrect customs, traditions, and cultural practices of the people. Due to this, the Prophet(s) said, “Be steadfast (in your actions) and do not count (your good actions, which may cause you to limit them). And know that the best of your actions is the Prayer, and none except the Believer takes care to maintain his wudu”.
It was said, “al-Istiqamah is a trait such that with it all the good qualities are perfected, and without it all are disfigured.” Al-Wasiti (rh).