An-Nahl - 16:94

وَلاَ تَتَّخِذُواْ أَيْمَانَكُمْ دَخَلاً بَيْنَكُمْ فَتَزِلَّ قَدَمٌ بَعْدَ ثُبُوتِهَا وَتَذُوقُواْ الْسُّوءَ بِمَا صَدَدتُّمْ عَن سَبِيلِ اللّهِ وَلَكُمْ عَذَابٌ عَظِيمٌ
[16:94]
And do not make your oaths a means of deceit between you, lest a foot should slip after its stability and you should taste evil because you turned away from Allah's way and grievous punishment be your (lot).
And take not your oaths, to practise deception between yourselves, with the result that someone's foot may slip after it was firmly planted, and ye may have to taste the evil (consequences) of having hindered (men) from the Path of Allah, and a Mighty Wrath descend on you.
Make not your oaths a deceit between you, lest a foot should slip after being firmly planted and ye should taste evil forasmuch as ye debarred (men) from the way of Allah, and yours should be an awful doom.