All major religions basically teach the same core truths — be kind, love your neighbor — so it doesn't really matter which one, if any, you follow.

Why people find it persuasive

There is real overlap in the ethical teaching of major world religions (versions of the golden rule appear widely), and it feels tolerant, humble, and generous to treat them as different paths up the same mountain rather than competing exclusive claims.

Important distinctions

• • Shared ethical overlap vs. shared metaphysical and theological claims.
• • Surface-level moral similarity vs. deep and often flatly contradictory claims about God, salvation, the afterlife, and the nature of reality.
• • Genuine religious pluralism as a philosophical position vs. a popular but under-examined slogan.
• • Respecting adherents of other religions vs. treating their specific truth claims as interchangeable with one's own.

Christian response

• • Grant the true part generously: many religious traditions do converge on general ethical principles like compassion, honesty, and some version of reciprocity, and this convergence is itself interesting and worth taking seriously (some Christian thinkers, following Romans 2, see it as evidence of a moral law written on the human conscience) — this concession costs nothing and should be made warmly.
• • But show concretely that this ethical overlap sits alongside sharp, direct, and often flatly incompatible claims at the level of core theology: Christianity claims one triune personal God who became incarnate and rose bodily from the dead; Islam explicitly and emphatically denies both the Trinity and Christ's crucifixion and divinity (Quran 4:157, 5:73); Buddhism in its classical forms denies a personal creator God and even a permanent individual self (anatta); Hinduism includes a spectrum from strict monism to personal theism; these are not differently-worded versions of one claim but logically incompatible claims about the most basic questions (is there a personal God, did Jesus die on the cross, is there an enduring self) — they cannot all be true simultaneously.
• • Point out that the 'all paths up the same mountain' image is not itself neutral — it is a substantive philosophical claim (a form of religious pluralism, associated with thinkers like John Hick) that most of the religions it describes explicitly reject as a description of their own teaching; ironically, treating all religions as saying the same thing requires overriding what most of them actually and explicitly claim about themselves, which is a strange way to show respect for them.
• • Note that genuine respect for other religious traditions is better served by taking their actual, specific truth claims seriously enough to engage them (and letting adherents of other faiths do the same with Christianity) rather than flattening everything into a vague common ethical residue that erases what each tradition actually holds to be true and important, including matters its own adherents regard as central rather than peripheral.
• • Distinguish this concern about competing truth-claims from a separate pastoral point: recognizing genuine disagreement between religions does not require personal hostility, disrespect, or a claim to certainty about every individual adherent's spiritual state — Christian teaching can hold both that ultimate truth claims are exclusive and that individual people of other faiths (and no faith) are to be treated with real respect, honesty, and love.

Christian counterresponse

Critics of this view (including philosophers like Alvin Plantinga in his critique of Hick) point out it is not actually neutral between the religions either — it requires each tradition to give up its own claim to be describing ultimate reality directly and accurately (something virtually every tradition it purports to include explicitly rejects about its own teaching), so pluralism ends up being a distinct sixth position that no actual religion holds, rather than a genuinely neutral synthesis of the others.