وَلَا تُصَعِّرْ خَدَّكَ لِلنَّاسِ وَلَا تَمْشِ فِي الْأَرْضِ مَرَحًا... وَاقْصِدْ فِي مَشْيِكَ وَاغْضُضْ مِن صَوْتِكَ ۚ إِنَّ أَنكَرَ الْأَصْوَاتِ لَصَوْتُ الْحَمِيرِ

In the present age, the progress of science has proved that distances and barriers are relative terms. ‘X’ rays are able to look into the interior of the body. The telescope and the microscope make such objects visible as cannot be seen by the naked eye. These possibilities which we experience in a limited fashion in the present world, exist with God on an unlimited scale. To follow religion or to call others to follow religion are both patience-trying tasks. While performing them, one has to think deeply before (following a course of) action, and one has to go against one’s own desires instead of pursuing them. One has unilaterally to surrender one’s ego instead of protecting it. One has to bear the troubles inflicted by others. All these tasks require the utmost courage, and the other name for courageous character is Islamic character.

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (31:18)