وَ رُوِيَ عَنِ النَّبِيِّ صَلَّي اللهُ عَلَيْهِ وَ آلِهٖ أَنَّهُ قَالَ أُمَّتِي أُمَّتِي إِذَا اخْتَلَفَ النَّاسُ بَعْدِي وَ صَارُوا فِرْقَةً فِرْقَةً فَاجْتَهِدُوا فِي طَلَبِ الدِّينِ الْحَقِّ حَتَّى تَكُونُوا مَعَ أَهْلِ الْحَقِّ فَإِنَّ الْمَعْصِيَةَ فِي دِينِ الْحَقِّ تُغْفَرُ وَ الطَّاعَةَ فِي دِينِ الْبَاطِلِ لَا تُقْبَلُ
It is reported that the Messenger of Allah (peace be on him and his progeny) said,
“My nation! My nation! When people differ after me and become into several groups, then all of you strive hard in seeking the true religion till you be with the people of truth. For, definitely, disobedience (sins) in the religion of truth will be forgiven but obedience in the religion of falsehood will not be accepted.”
References:
1. Jaame’ al-Akhbaar, p. 178, Chapter 141
2. Behaar al-Anwaar, vol. 27, p. 197, H. 58
3. Mustadrak al-Wasaael, vol. 1, p. 169, H. 274
Notes:
1) The Messenger of Allah (peace be on him and his progeny) has prophesied in several narrations that his nation will be split into several groups.
2) “Seventy-three sects” is only indicative to show plenty because we see far more sects and sub-sects among Muslims today than can be counted.
3) The above narration emphasizes that “strive” i.e. spend all your energy to find the religion of truth and bear all sorts of difficulties in this path till you meet the people of truth.