Following are a number of back-translations of Mark 11:17:

• Uma: “He taught them, he said: ‘Don’t you know what is written in the Holy Book? God said like this: ‘My house will become a prayer house used by people all over the world.’ Yet you [emphatic], you have treated it like the house of robbers!'” (Source: Uma Back Translation)
• Yakan: “Isa preached/taught, he said to the people, ‘It is written in the holy-book, God says, ‘My house is called a house for praying (of) all tribes.’ But you,’ said Isa, ‘you have made the house of God like a house for thieves to hide in.'” (Source: Yakan Back Translation)
• Western Bukidnon Manobo: “Then he taught the people there, he said, ‘There is a written word of God which says, ‘As for my house, it shall be called a house of prayer for all people of every kingdom.’ But as for you,’ said Jesus, ‘you have made it a place where cheaters live.'” (Source: Western Bukidnon Manobo Back Translation)
• Kankanaey: “Then he taught the many-people and said, ‘It is written in the word of God, ‘My house, it will-be-called a praying-place for people.’ But as for you, you have changed it to a place-where-you -cheat your fellows!'” (Source: Kankanaey Back Translation)
• Tagbanwa: “And then he taught the people saying, ‘Isn’t it so that it’s contained there in the written word of God, ‘The house where I am worshipped is to be called a house of prayer for all nations’? But you have made it a nest of thieves!'” (Source: Tagbanwa Back Translation)

For the Old Testament quote, see Jeremiah 7:11 and Isaiah 56:7.