Inclusivism, one of several approaches to understanding the relationship between religions, asserts that while one set of beliefs is absolutely true, other sets of beliefs are at least partially true. It stands in contrast to exclusivism, which asserts that only one way is true and all others are in error, and pluralism, which asserts that all beliefs are equally valid within a believer's particular context.

Broadly speaking, there are two schools of Inclusivist thought:

• Traditional Inclusivism, which asserts that the believer's own views are absolutely true, and believers of other religions are correct insofar as they agree with that believer.
• Relativistic Inclusivism, which asserts that an unknown set of assertions are Absolutely True, that no human being currently living has yet ascertained Absolute Truth, but that all human beings have ascertained Absolute Truth to one degree or another.

Strands of both types of Inclusivist thought of both types run through all faiths.

Inclusivist thought in Christianity

Jesus, the founder of Christianity, said, "He who is not against me is for me." Mark 9:40. The belief is affirmed by the aphorism common in some Christian circles, affirming that "All Truth is God's Truth."

Inclusivist thought in Islam

The Quran, revealed through Muhammed, states, "Those with Faith, those who are Jews, and the Christians and Sabaeans, all who have Faith in Allah and the Last Day and act rightly, will have their reward with their Lord. They will feel no fear and will know no sorrow." (Quran, Surat al-Baqara; 2:62)

Say, 'People of the Book! come to a proposition which is the same for us and you - that we should worship none but Allah and not associate any partners with Him and not take one another as lords besides Allah.' If they turn away, say, 'Bear witness that we are Muslims.'(Surah Al 'Imran; 3:64)

Today all good things have been made halal for you. And the food of those given the Book is also halal for you and your food is halal for them. So are chaste women from among the muminun and chaste women of those given the Book before you, once you have given them their dowries in marriage, not in fornication or taking them as lovers. But as for anyone who rejects iman, his actions will come to nothing and in the akhira he will be among the losers. (Surat al-Ma'ida: 5:5)

Among the people of the Book there are some who have iman in Allah and in what has been sent down to you and what was sent down to them, and who are humble before Allah. They do not sell Allah's Signs for a paltry price. Such people will have their reward with their Lord. And Allah is swift at reckoning. (Surah Al 'Imran; 3:199)

Call to the way of your Lord with wisdom and fair admonition, and argue with them in the kindest way. Your Lord knows best who is misguided from His way. And He knows best who are guided. (Surat an-Nahl; 16:125)

...You will find the people most affectionate to those who have iman are those who say, 'We are Christians.' That is because some of them are priests and monks and because they are not arrogant. (Surat al-Ma'ida; 5:82)

Only argue with the People of the Book in the kindest way - except in the case of those of them who do wrong - saying, 'We have iman in what has been sent down to us and what was sent down to you. Our God and your God are one and we submit to Him.'(Surat al-'Ankabut; 29:46)

...There is a community among the People of the Book who are upright. They recite Allah's Signs throughout the night, and they prostrate. They have iman in Allah and the Last Day, and enjoin the right and forbid the wrong, and compete in doing good. They are among the salihun. You will not be denied the reward for any good thing you do. Allah knows those who have taqwa. (Surah Al 'Imran: 3:113-115)

Inclusivist thought in Hinduism

• A well-known Rig Vedic hymn stemming from Hinduism claims that "Truth is One, though the sages know it variously."