Is the supplication: "O Allah, I have completely and entirely surrendered to You, and I have placed my destiny in Your hands, O Allah, O Powerful, O Compeller, O Most Generous. For I am in complete certainty that You will not forsake me as long as I put my trust in You, O Allah," free of linguistic errors?

The wording of this supplication contains no linguistic or Sharia errors, and its content is found in authentic hadiths. The Prophet, peace and blessings be upon him, used to say in his Tahajjud (night vigil prayer): "O Allah, to You I have submitted, in You I have believed, upon You I have relied, to You I have turned in repentance, and by Your help I have disputed." The meaning of "I have submitted" is that I have surrendered and yielded to Allah's command. The meaning of "I have relied" is that I have entrusted the matter to Him, which is expressed as "I have placed my destiny in Your hands." It is preferable to supplicate with the ma'thur (transmitted) supplications because they are superior and more comprehensive.