All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
We do not know any evidence from the Sunnah that legislates reading some special verses at some special occasions except in Khubatul-Haajah [the introduction before any religious speech] which the Prophet used to say in his Friday speeches, in marriage ceremonies and other occasions. He used to say the two testimonies of faith and then read three verses. The first verse is the Saying of Allaah (which means): {O mankind, fear your Lord, who created you from a single soul (Aadam ) and created from it [from him] its mate [Hawwaa’ (Eve)] and dispersed from both of them many men and women. And fear Allaah, through whom you ask one another, and the wombs. Surely, Allaah is ever an All-Watcher over you.}[Quran 4:1]. The second verse is the Saying of Allaah (which means): {O you who have believed, fear Allaah as He should be feared and do not die except as Muslims [in submission to Him].}[Quran 3:102]. The third verse is the Saying of Allaah (which means): {O you who have believed, fear Allaah and speak words of appropriate justice. He will [then] amend for you your deeds and forgive you your sins. And whoever obeys Allaah and His Messenger has certainly achieved a great acheivement.}[Quran 33:70-71][At-Tirmithi and Al-Bayhaqi]
It is reported that Shu’bah asked Abu Is-Haaq: 'Is this at marriage ceremonies, or other ceremonies?” He replied: ''It is said in all religious speeches.'
As regards reading verses at some occasions without any Khutbah (speech), then we do not know any evidence from the Sunnah proving this.
Allaah Knows best.