(defun c:tst (/ SS N I E1 S1 S12 E2 TH)
 (setq ss (ssget))
 (setq st (getstring "\nEnter New Text Style: "))
 (setq n (sslength ss))
 (setq i 0)
  (repeat n
   (setq e1 (entget (ssname ss i)))
   (setq i (+ i 1))
   (setq s1 (assoc 0 e1))
   (if (= "TEXT" (cdr s1))
    (progn
     (setq s12 (assoc 7 e1))
     (setq e2 (subst (cons 7 ST) s12 e1))
     (entmod e2)
    )
   )
  )
 (princ)
)