The Hindus have a saying that states that 'Guests are God'. I was invited to a Hindu household once, but I did not go because I believed that there was a real chance that this was Shirk (polytheism) as by going I would be allowing them to equate me with, and treat me as, God. I constantly thought about ways in which it would not be Shirk and wondered if it actually was. I felt disappointed regarding what I was missing by not going. Thinking about this, I suddenly, out of frustration, remarked to myself, "Do you realize how much madness you have gotten into?" (by becoming so religious.) Is this Kufr (disbelief) as I called refraining from a possible act of Kufr 'madness'? Finally, can you also advise me on whether it would be Kufr to go to a Hindu household as a guest?

All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.

The attribute of divinity (being God) is a unique attribute exclusively of Allah, The Exalted, and it cannot be attributed to any other than Him. Ibn Jareer At-Tabari wrote in his Tafseer (exegesis) that Ibn ‘Abbaas, may Allah be pleased with him, said, "Allah is the one possessing divinity and the right to be worshiped over His entire creation."

Attributing divinity to a created being is an act of Shirk; however, it is an act of Shirk on part of the one who attributes it to another created being, i.e. the host in your question, and not the described person himself (the guest).

There is no religious objection to visiting a non-Muslim person, especially if on hopes to encourage him to embrace Islam. Anas, may Allah be pleased with him, narrated that a young Jewish boy, who was in the service of the Prophet, sallallahu ‘alayhi wa sallam, fell ill. The Prophet went to visit him, sat down by his head, and said to him, "Embrace Islam." The little boy looked at his father who was sitting beside him. He said, "Obey Abul-Qaasim (i.e., the Messenger of Allah, sallallahu ‘alayhi wa sallam)." So he embraced Islam and the Prophet, sallallahu ‘alayhi wa sallam, stepped out, saying, "Praise be to Allah, Who has saved him through me from Hellfire." [Al-Bukhari]

Hence, it is not prohibited for the Muslim to visit non-Muslims, let alone that such an act would be Kufr (disbelief). Describing not visiting him as 'madness' is not Kufr at all. It should be noted, though, that it is impermissible for the Muslim to take non-Muslims as close friends and allies (instead of Muslims); Allah, The Exalted, says (what means): {O you who have believed, do not take My enemies and your enemies as allies, extending to them affection while they have disbelieved in what came to you of the truth...} [Quran 60:1]

Describing oneself or another person as a Kaafir (disbeliever) is a grave and serious matter. This matter must not be taken lightly; it must be governed by the Sharia texts. Shaykh Ibn ‘Uthaymeen said:

"It is impermissible to declare a specified Muslim a Kaafir until two conditions are met: The first, that the evidence that what he said or did is Kufr that takes the doer out of the fold of Islam is established. If the matter is doubted and it is not known with certainty, it is impermissible to declare him a Kaafir, and the basic principle is that he is a Muslim. The second, verifying that the ruling of Kufr applies to that person so that he meets the conditions of Takfeer (declaring him a Kaafir)..."

Allah knows best.