Unwavering faith and conviction in monotheism

وَحَآجَّهُۥ قَوْمُهُۥ ۚ قَالَ أَتُحَـٰٓجُّوٓنِّى فِى ٱللَّهِ وَقَدْ هَدَىٰنِ ۚ وَلَآ أَخَافُ مَا تُشْرِكُونَ بِهِۦٓ إِلَّآ أَن يَشَآءَ رَبِّى شَيْـًٔا ۗ وَسِعَ رَبِّى كُلَّ شَىْءٍ عِلْمًا ۗ أَفَلَا تَتَذَكَّرُونَ

And his people argued with him. He said, "Do you argue with me concerning Allāh while He has guided me? And I fear not what you associate with Him [and will not be harmed] unless my Lord should will something. My Lord encompasses all things in knowledge; then will you not remember?