Translation:

23. There will then be (left) no subterfuge for them but to say: "By Allah Our Lord we were not those who joined gods with Allah."

Notes (Tafseer)

851. Fitnat has various meanings, from the root idea of "to try , to test, to tempt;" e.g. (1) a trial or temptation, as in ii. 102; (2) trouble, tumult, oppression, persecution, as in ii. 191, 193, 217; (3) discord, as in iii. 7; (4) subterfuge, an answer that amounts to a sedition, and excuse founded on a falsehod, as here. Other shades of meaning wll be noticed as they occur. Those who blasphemed God in imagining false gods will now see the vanity of their imaginations for themselves. What answer can they give now? In their perverisity they will deny that they ever entertained the notion of false gods.