‘This is the first I’ve heard of it, you mustn’t take everything that man says as gospel!’
This means, as you’ve probably guessed, to believe something without questioning or doubting it at all (never a good thing!) A nice synonym would be to take at face value.
– However, take this as gospel: you have never seen traffic until you go to Lagos in Nigeria (The Guardian).
– Marshall says “it is based on a true story”, but says “you shouldn’t take this as Gospel fact” (The Guardian).
– There are those who take as gospel everything that appeared in the composer’s much-disputed volume of memoirs, Testimony, taking it as licence to interpret all his major works as coded acts of dissent against the Soviet regime, and there are those who regard the man’s life and his music as separate, and take what he composed at face value (The Guardian).