Let us consider just three ways. First, by wholeheartedly sharing in the preaching work. Christ commanded his brothers to preach the good news worldwide.
فَكَيْفَ تُظْهِرُ أَنَّكَ صَدِيقٌ لِإِخْوَةِ ٱلْمَسِيحِ إِذَا كُنْتَ تَرْجُو ٱلْحَيَاةَ عَلَى ٱلْأَرْضِ فِي ظِلِّ مَلَكُوتِ ٱللهِ ؟‏