Following are a number of back-translations of Romans 1:20:

• Uma: “For even though we cannot see the appearance of God, from the beginning of the making of the world it has been knowable/evident to men what God is like. For from all that he made, we see the bigness of his life [i.e., glory] and we also see his power that has no end. So there is no one who can say: ‘I didn’t know!'” (Source: Uma Back Translation)
• Yakan: “Since (the time) the world was created by God, it is clear to the people that God has power that doesn’t leave even if they cannot/didn’t happen-to-see his power and it is also clear to them that he is the true God even though they cannot see him. The people can understand about God and about his power by the various-things he has created. That’s why they cannot give excuses/excuse themselves for/because-of their deeds.” (Source: Yakan Back Translation)
• Western Bukidnon Manobo: “For as for God, even though He cannot be seen, beginning from His creation of the world, He is apparent just the same by means of all the things that he created by means of His very great power which has no end, and by means of what is called His being God. That’s why nobody can say they do not know whether there is a God.” (Source: Western Bukidnon Manobo Back Translation)
• Kankanaey: “Because since-the-time when God created the world, it has been easy for people to understand concerning his godhood and his power which has no limit, even though he cannot be seen, because what he created can be seen. So they have absolutely no excuse for not knowing the truth.” (Source: Kankanaey Back Translation)
• Tenango Otomi: “And now, no one sees God, but that which he made is what we see. From this it is apparent that God lives. When the world began to exist, then it was apparent that God lives and that he has his power forever. It isn’t possible then that people say that they do not know that God lives.” (Source: Tenango Otomi Back Translation)
• Isthmus Zapotec: “Even though we cannot see the power of God which shall never end, nor can we see what he is like, yet from the day the world was created it has been clearly seen who he is (or what he is like) because of all he has done. Therefore they cannot say they do not know.”
• Hopi: “For people understand clearly the things about God that are unseen. He alone is God and continually has power. And the people understand who he is and that he has power through the things here that are made. Since the time that the world was made they understood these things and therefore they have no way of escape.”
• Central Mazahua: “What God is and his power no one can see with their eyes. But they can know [in their thoughts] because it is seen in the things that God made since the world was made. Therefore when God will judge them they can’t say they didn’t know how he is.” (Source for this and two above: Waterhouse / Parrott in Notes on Translation October 1967, p. 1ff.)

For the Old Testament quote, see Psalm 69:22 and Psalm 69:23.