Al-Ma'idah 5:61

Wa-itha jaookum qaloo amannawaqad dakhaloo bilkufri wahum qad kharajoo bihi wallahuaAAlamu bima kanoo yaktumoon

And when they come to you, they say, "We believe." But they have entered with disbelief [in their hearts], and they have certainly left with it. And Allāh is most knowing of what they were concealing.

When they come to you, they say, “We believe”, while with disbelief they came in, and with the same (disbelief) they went out. Allah knows best what they used to conceal.