How to do confirmation signin to confirm the password is true with fireauth

Firstly i want to check the password and email is true with fireauth. If the password is false not same with fireauth, that will popup toast.

 firebaseAuth.signInWithEmailAndPassword(email,password)
            .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    progressDialog.dismiss();
                    if(task.isSuccessful()){
                        finish();
                        if(!password.equals()){

                        }
                        userVerified();
                    }else{
                        Toast.makeText(Signin.this, "Your account not registered",Toast.LENGTH_LONG).show();
                        startActivity(new Intent(getApplicationContext(),Signup.class));
                    }
                }
            });
}

i stuck on password.equals. i don't know how to match with fireauth.