Is it considered disbelief for a Muslim woman who conceals her Islam from her Christian family to tell them she is Christian?

We congratulate the questioner on her guidance to Islam and give her glad tidings of two rewards. It is clear that confronting family and non-Muslim society is a great trial, especially in Eastern countries, and these fears should motivate the new Muslim to steadfastness and determination to continue on the path of guidance. The question allows for concealing one's Islam and pretending to continue in the former religion when under duress and fearing trial, citing the verse: "except for one who is forced [to recant] while his heart is at peace with faith," and the incident of Ammar ibn Yasir. It advises the questioner, when she says she is "Christian," to intend that she is a follower of Christ Jesus, peace be upon him, who was a Muslim and a harbinger of Islam, and not of the religion of the cross. It emphasizes the permissibility of concealing Islam until Allah brings relief and a way out.