It is narrated from Sayyiduna Nu’man bin Bashir (may Allah be pleased with them both), who reports from the Prophet Muhammad (peace and blessings be upon him) that indeed supplication is worship. Then the Prophet (peace and blessings be upon him) recited (the verse): ﴿وَقَالَ رَبُّكُمُ ادْعُونِي أَسْتَجِبْ لَكُمْ﴾ (Al-Mu’min: 60)“And your Lord said: Call upon Me; I will respond to you.”