Allah orders His Messenger to say to mankind and the Jinns that this is his way, meaning, his method, path and Sunnah, concentrating on calling to the testimony that there is no deity worthy of worship except Allah alone without partners. The Messenger ﷺ calls to this testimonial with sure knowledge, certainty and firm evidence. He calls to this way, and those who followed him call to what Allah's Messenger ﷺ called to with sure knowledge, certainty and evidence, whether logical or religious evidence,
وَسُبْحَانَ اللَّهِ
(And Glorified and Exalted be Allah.) This part of the Ayah means, I glorify, honor, revere and praise Allah from having a partner, equal, rival, parent, son, wife, minister or advisor. All praise and honor be to Allah, glorified He is from all that they attribute to Him,
تُسَبِّحُ لَهُ السَّمَـوَتُ السَّبْعُ وَالاٌّرْضُ وَمَن فِيهِنَّ وَإِن مِّن شَىْءٍ إِلاَّ يُسَبِّحُ بِحَمْدَهِ وَلَـكِن لاَّ تَفْقَهُونَ تَسْبِيحَهُمْ إِنَّهُ كَانَ حَلِيمًا غَفُورًا
(The seven heavens and the earth and all that is therein, glorify Him, and there is not a thing but glorifies His praise. But you understand not their glorification. Truly, He is Ever Forbearing, Oft-Forgiving.) 17:44)