ذَلِكَ أَدْنَى أَن يَأْتُواْ بِالشَّهَادَةِ عَلَى وَجْهِهَا أَوْ يَخَافُواْ أَن تُرَدَّ أَيْمَانٌ بَعْدَ أَيْمَانِهِمْ وَاتَّقُوا اللّهَ وَاسْمَعُواْ وَاللّهُ لاَ يَهْدِي الْقَوْمَ الْفَاسِقِينَ
[5:108]
This is more proper in order that they should give testimony truly or fear that other oaths be given after their oaths; and be careful of (your duty to) Allah, and hear; and Allah does not guide the transgressing people.
That is most suitable: that they may give the evidence in its true nature and shape, or else they would fear that other oaths would be taken after their oaths. But fear Allah, and listen (to His counsel): for Allah guideth not a rebellious people:
Thus it is more likely that they will bear true witness or fear that after their oaths the oaths (of others) will be taken. So be mindful of your duty (to Allah) and hearken. Allah guideth not the froward folk.