(Maryam) 19 : 36
وَإِنَّ اللَّهَ رَبِّي وَرَبُّكُمْ فَاعْبُدُوهُ ۚ هَٰذَا صِرَاطٌ مُسْتَقِيمٌ
“And indeed, Allah is my Lord and your Lord; so you serve Him, that is the Straightpath".
All 313 Messengers are sent down with the Truth and Proof Adhikr to teach mankind that there is no deity besides Lord Allah and to serve Him alone as explained in verses 21: 24-25. See explanation 3: 47-51.