Sayyiduna Abdullah bin Sarjis (may Allah be pleased with him) narrates: A man entered the mosque after the iqamah had been pronounced while the Prophet Muhammad (peace and blessings be upon him) was performing the prayer. This man performed two rak‘ahs and then joined the row. When the Prophet (peace and blessings be upon him) had completed the prayer, he asked: Which of the two have you counted? (The narrator is in doubt, perhaps these are the words:) Through which of the two do you hope for reward now? The prayer which you performed with us, or the prayer which you performed alone?
Hadith Referenceصحیح ابن حبان / كتاب الصلاة / 2191
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «الصحيحة» (2588): م.فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح، عبد الله بن معاوية لم يخرجا له، وهو ثقة، ومن فوقه من رجال الشيخين غير صحابيه، فإنه من رجال مسلم.