Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah ﷺ used to urge (the people) to perform (optional Tarawih) prayer at night during the month of Ramadan. He did not order them or make it obligatory on them. He ﷺ said, "Whosoever performs (optional Tarawih) prayers at night during the month of Ramadan, with Faith and in the hope of receiving Allah's reward, will have his past sins forgiven."

[Muslim].

وعنه، رضي الله عنه قال: كان رسول الله ﷺ، يرغب في قيام رمضان من غير أن يأمرهم فيه بعزيمة، فيقول: "من قام رمضان إيمانًا واحتسابًا غفر له ما تقدم من ذنبه" . ((رواه مسلم)).