Sometimes, while we are talking to non-muslims such as christians we may hear them call on Prophet Jesus (peace be upon him) instead of Allaah. Does this fall under the verse of the Quran where Allaah says that we should not sit with those who mock our religion and verses? Is it permissible to talk to them?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger. 

It is permissible for a Muslim to attend the meetings of the non-Muslims and talk to them and discuss with them about ordinary matters that are not related to disbelief, such as buying and selling, and so forth. As regards the meetings where they worship other than Allaah, it is not permissible to attend them, as Allaah says (what means): {And it has already come down to you in the Book that when you hear the verses of Allaah [recited], they are denied [by them] and ridiculed; so do not sit with them until they enter into another conversation. Indeed, you would then be like them. Indeed Allaah will gather the hypocrites and disbelievers in Hell all together.} [Quran 4:140]

This applies if he does not forbid them from disbelief with his tongue provided he is able to do so, or deny it with his heart and leave them. If he is unable to do all this, then there is no harm on him and he is not sinful just because of sitting with them as long as he denies evil with his heart; At-Tabari said in his Tafseer:

“As for the interpretation of the saying of Allaah (which means): {And those who fear Allaah are not held accountable for the disbelievers at all, but [only for] a reminder – that perhaps they will fear Him.} [Quran 6:69], then Allaah says: If someone fears Allaah and obeys him in what He commands him to do and shuns off what He has forbidden him to do, then he should not fail to avoid those who are engaged in mocking the Verses of Allaah at the time they are ridiculing the Verses of Allaah in regard to something between him and Allaah; if failing to avoid them does not constitute being satisfied with what they do, while he is fearing the Rights of Allaah, he will be innocent of them and he will have saved himself from their sin but he should avoid sitting with the wrongdoers in this case; {but a reminder} means of the Command of Allaah, that perhaps they will fear Him} Allaah says: so that they should fear him … Their avoidance is a reminder of the Command of Allaah so that they may fear Him. It was reported that the Prophet was ordered to leave the non-Muslims (polytheists) at the time they ridicule the verses of Allaah, because they hated that he would stand and leave their meeting, so Allaah told him: If they mock the verses of Allaah, then do not sit with them so that they should avoid mocking His Verses and stop doing so…”

Shaykh Ibn Taymiyyah said:

“A believer must fear Allaah in His slaves, but he is not required to guide them (i.e. guarantee that they would obey Allaah), and this is the meaning of the verse in which Allaah says (what means): {O you who have believed, upon you is [responsibility for] yourselves. Those who have gone astray will not harm you when you have been guided.} [Quran 5:105]; being guided is achieved by fulfilling the obligation, so if a Muslim fulfills the order of enjoining good and forbidding evil, in the same manner he fulfills other obligations, then the misguidance of the people who have gone astray would not harm him. This is done sometimes by the heart, and sometimes by the tongue, and sometimes by hand. Denying or detesting by one’s heart is a must in all cases as there is no harm in doing so, and if someone does not do it, then he is not a believer, as  the Prophet said, 'This is the lowest – or weakest – level of Faith.'” [Majmoo' Al-Fataawa]

As-Sa'di said: 

“This prohibition applies to those who sit with them (the disbelievers) and do not fear Allaah, like if one takes part in their discussion and forbidden act, or that he keeps silent and does not deny what they do. If he expresses piety of Allaah, such as ordering them to do good and forbidding them from doing evil and from saying the statements that they say, and this leads to the disappearance of evil, or at least its diminution, then there is no harm on such a person or sin; it is for this reason that Allaah says: {And those who fear Allaah are not held accountable for the disbelievers at all, but [only for] a reminder – that perhaps they will fear Him.} [Quran 6:69]; meaning that this reminder would remind them and admonish them so that they might fear Allaah.”

The scholars of the Standing Committee said:

“It is permissible that we gather with the non-Muslims in the general meeting places that the government has set up and organized for debates and scientific seminars and for delivering lectures on religious affairs, provided that the Muslim scholars who attend clarify the creed of Islam, its pillars and its etiquette, and refute the misconceptions that the audience of other religions raise about Islam, and demonstrate that their articles by which they distort Islam are false ... and other matters by which they defend the truth.

As regards the Muslims of whom it is feared that they might be tempted in their religion due to their ignorance or weakness in their readiness and thinking or lack in their knowledge about their religion, then they are not permitted to attend these meetings and similar ones; as a way of preserving them from temptation and out of fear that doubts or misconceptions would affect them.”

Allaah knows best.