If I join the imam while he is bowing, have I caught the rak‘ah?

Original answer — Shaykh ‘Abd al-‘Aziz ibn Baz

Question

«إذا أدرك المسبوق الإمام راكعًا فما المشروع له حينئذ؟ وهل يشترط للحكم بإدراكه الركعة أن يقول: سبحان ربي العظيم قبل رفع الإمام؟»

English translation (unreviewed): If the latecomer catches the imam in ruku', what is prescribed for him then? And is it a condition for judging that he has caught the rak'ah that he says 'Subhana Rabbiyal-'Azim' before the imam rises?

From the text of the answer

«إذا أدرك المأموم الإمام راكعًا أجزأته الركعة ولو لم يسبح المأموم إلا بعد رفع الإمام؛ لعموم قوله ﷺ : من أدرك ركعة من الصلاة فقد أدرك الصلاة [١] خرجه مسلم في صحيحه. ومعلوم أن الركعة تدرك بإدراك الركوع؛ لما روى البخاري في صحيحه عن أبي بكرة الثقفي أنه أتى المسجد ذات يوم والنبي ﷺ راكع فركع دون الصف ثم دخل في الصف فلما سلم النبي ﷺ قال له ﷺ : زادك الله حرصًا ولا تعد ولم يأمره بقضاء الركعة، وإنما نهاه أن يعود إلى الركوع دون الصف، فعلى المسبوق ألا يعجل بالركوع حتى يدخل في الصف [٢] .»

English translation (unreviewed): If the follower catches the imam in ruku', the rak'ah counts for him even if the follower does not glorify Allah until after the imam rises, because of the general saying of the Prophet ﷺ: “Whoever catches a rak'ah of the prayer has caught the prayer” [1], reported by Muslim in his Sahih. It is known that the rak'ah is caught by catching the ruku', for what al-Bukhari reported in his Sahih from Abu Bakrah al-Thaqafi, that he came to the mosque one day while the Prophet ﷺ was in ruku', so he bowed before reaching the row, then joined the row. When the Prophet ﷺ gave the salam, he said to him: “May Allah increase you in eagerness, but do not repeat it.” He did not order him to make up the rak'ah; he only forbade him from returning to the ruku' before the row. So the latecomer should not hurry to ruku' until he enters the row [2].