(Muhammad Assad)
63:3 this, because [they profess that] they have attained to faith, whereas [inwardly] they deny the truth - and so, a seal has been set on their hearts so that they can no longer understand [what is true and what false]. 63:3
(Yousaf Ali)
63:3 That is because they believed, then they rejected Faith: So a seal was set on their hearts: therefore they understand not.63:3