«لا يكون لمسلم أن يهجر مسلما فوق ثلاثة فإذا لقيه سلم عليه ثلاث مرات كل ذلك لا يرد عليه فقد باء بإثمه»
The Prophet (peace and blessings be upon him) said:
"It is not permissible for a Muslim to stay estranged from a Muslim for more than three days. So when he meets him and greets him with salam three times, and each time he does not reply, then (the one who refuses to reconcile) returns with his own sin."
Hadith Referenceصحیح الجامع الصغیر / حرف اللام ألف / 7775