(And) connects this verse with the previous one, meaning it is related to the priests and monks. As has been mentioned before; Allah (swt) has outlined for the nation the line of enmity; that the most intense in enmity are mainly the Jews. This is proven by what we see today. Ever since the revelation of the message unto the heart of the Prophet Muhammad (saws), the conspiration of the Jewish Zionists has been on-going, albeit in different ways and with Arabian and Western collusions. Due to this, Allah (swt) put them together with the Jews in this verse, and He mentioned the Jews before the polytheists. However, He (swt) willed to differentiate between the People of the Book with regards to their relationship with the Muslims. So, He (swt) placed the relationship between the Muslims and Christians within the framework of cordiality, which is the greatest framework that exists between people.
(… وَإِذَا سَمِعُوا مَا أُنزِلَ إِلَى الرَّسُولِ تَرَىٰ أَعْيُنَهُمْ تَفِيضُ مِنَ الدَّمْعِ ) (And when they hear what has been revealed to the Messenger, you see their eyes overflowing with tears …): The Holy Quran has preceded modern-day knowledge in matters connected to psychology and its effect on the functionality of the organs. Among the issues connected to psychology are perception, conscience and impulse. Allah (swt) explains all of these in this verse by saying: (And when they hear), indicating that they are perceiving through the sense of hearing, which is one of the tools of perception. The other tool is the sight (their eyes overflowing with tears), this points to the effect this thing which they had heard on the conscience, represented by the tears.
( يَقُولُونَ رَبَّنَا آمَنَّا فَاكْتُبْنَا مَعَ الشَّاهِدِينَ… ) (…They say, “Our Lord, we have believed, so register us among the witnesses.): Meaning, make us among those who bear witness on the Day of Judgement of this faith and this Noble Prophet (saws).