"[And that you do not exalt yourselves against Allah]" means: Do not act arrogantly regarding the worship of Allah. "[Indeed, I come to you]" means: I have indeed come to you, "[with clear authority]" with a manifest proof.
﴿وَأَنْ لَا تَعْلُوا عَلَى اللَّهِ﴾ أَي: لَا تستكبروا عَن عبَادَة الله ﴿إِنِّي آتيكم﴾ أَي: قد أتيتكم ﴿بِسُلْطَانٍ مُبِينٍ﴾ بِحجَّة بَيِّنَة
