Ramchal in Derekh HaShem III 2 (7) speaks about using the names of G-d to achieve effects not achievable using physical agencies. He says,
א׳ הוא הזכרת שמו ית׳ כמי שקורא אותו שיענהו, וימשיך על ידי זה ממנו השפעה,
“One form is the mentioning of His name as one calls Him that He should answer and thus influence is drawn down” which sounds a bit like prayer.
But he also says, אינו ראוי והגון להדיוט שישתמש בשרביטו של מלך “It is not fitting for a plain person to use the sceptre of the King” which does not sound like prayer.
Is הפעולה בשמות or “theurgy” similar to prayer?