Marriage

It was narrated from Abu Hurairah (RA): that the Prophet (ﷺ) used to say when offering congratulations on the occasion of marriage: “Barak Allahu lakum, wa barak 'alaikum, wa jama'a bainakuma fi khair (May Allah bless you and bestow blessings upon you, and bring you together in harmony).”

(Sunan Ibn Majah 1905, Book 9, Hadith 61)

The dua in this Hadith is:

بَارَكَ اللَّهُ لَكُمْ وَبَارَكَ عَلَيْكُمْ وَجَمَعَ بَيْنَكُمَا فِي خَيْرٍ