They alter the Scripture, what Allah (swt) says, with their tongues to change its meaning. So, they used to alter the utterances and claim that they were part of what the Almighty (swt) said, although they are not so. However, they did that to underestimate Islam and challenge the Messenger (saws). Earlier, they said:

{ رَاعِنَا}

(Ra’ina.) (Al-Baqara: 104)

so, Allah the Almighty says addressing the believers:

 {يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تَقُولُوا رَاعِنَا وَقُولُوا انظُرْنَا وَاسْمَعُوا ۗ وَلِلْكَافِرِينَ عَذَابٌ أَلِيمٌ }

(O you who have believed, say not [to Allah ‘s Messenger], “Ra’ina” but say, “Unthurna” and listen. And for the disbelievers is a painful punishment.) (Al-Baqara: 104)

They also alerted (hitta) to (hinta) (in Arabic) to make us believe that such change is from the Scripture, but it is never so.