What is the ruling of Islamic law on a Muslim living in a European country who receives in-kind and financial aid from churches, while having a monthly income that suffices for him and his family? And is this aid considered unlawful?

The Prophet, peace and blessings be upon him, accepted gifts from disbelievers. Therefore, if the aid from the church is not intrinsically forbidden and does not compel a Muslim to compromise their religion, there is no harm in accepting it. However, if the aid is intrinsically forbidden or leads to something forbidden, then its provider must be enjoined from evil. It is preferable to refrain from accepting aid if a Muslim is not in need of it.