وَيَصْلُحُ لِلْإِلْزَامِ عَلَى الْغَيْرِ
And is suitable for establishing a binding case against someone else.
Ilzām means presenting evidence that an interlocutor can understand and that has force under shared standards of argument. Inspiration generally lacks this common, inspectable status. One party may say an inner disclosure affirms a judgment; another may report the opposite. The subjective certainty of each does not settle the conflict.
Especially where the rights of others, accusations, or religious obligations are concerned, personal reassurance must not be confused with an authoritative, mutually assessable proof. A claim about the heart alone cannot replace an established evidential standard.