اَللّٰهُمَّ أَلِّفْ بَيْنَ قُلُوبِنَا وَأَصْلِحْ ذَاتَ بَيْنِنَا وَاهْدِنَا سُبُلَ السَّلاَمِ وَنَجِّنَا مِنَ الظُّلُمَاتِ إِلَى النُّورِ وَجَنِّبْنَا الْفَوَاحِشَ مَا ظَهَرَ مِنْهَا وَمَا بَطَنَ وَبَارِكْ لَنَا فِي أَسْمَاعِنَا وَأَبْصَارِنَا وَقُلُوبِنَا وَأَزْوَاجِنَا وَذُرِّيَّاتِنَا وَتُبْ عَلَيْنَا إِنَّكَ أَنْتَ التَّوَّابُ الرَّحِيمُ وَاجْعَلْنَا شَاكِرِينَ لِنِعْمَتِكَ مُثْنِينَ بِهَا قَابِلِيهَا وَأَتِمَّهَا عَلَيْنَا

Allaahumma allif bayna quluubinaa, wa aslih dhaata bayninaa, wah-dinaa subulas-salaam(i), wa najjinaa minaz-zulumaati ilan-nuur(i), wa jannibnal-fawaahisha maa zahara minhaa wa maa batan(a), wa baarik lanaa fii asmaa’inaa wa absaarinaa wa quluubinaa wa azwaajinaa wa dhurriyyaatinaa, wa tub- ‘alaynaa, innaka antat-Tawwaabur-Rahiim(u), waj-‘alnaa shaakiriina lini’matik(a), muthniina bihaa qaabiliihaa, wa atimmahaa ‘alaynaa. (‘Abdullah ibn Mas’ud. Sunan Abi Dawud #825)

O Allah, join our hearts, mend our relationships, and guide us to the paths of peace. Bring us out of darkness into light and keep us away from manifest and  concealed obscenities. Bless us in our ears,our eyes, our hearts, our spouses, and our offspring. Accept our repentance. Indeed, You are the Most Forgiving, the Most Merciful. Make us grateful for  Your blessings, so we receive them with due praise. And perfect them for us.

Ameen

According to Sayyidna ‘Abdullah ibn Mas’ud (ra), Prophet Muhammad (sallallahu alayhi wa sallem) used to teach this du’aa to his Companions for saying in the salaat before the ending salaam.

(Source: Khalid Baig’s commentary to du’aa #57 in the Accepted Whispers: Munajat-e-Maqbul)