I just wandered to a website which was about converting to Islam. I got the link through an Ads displayed on YouTube. I read the website first page as fun.
Few lines from the website, which also mention the source of it are:
“...The only religion in the sight of God is Islam...” (Quran 3:19)
“If anyone desires a religion other than Islam, never will it be accepted of him; and in the Hereafter, he will be in the ranks of those who have lost (their selves in the Hellfire).” (Quran 3:85)
“Indeed God has forbidden to reside eternally in Hell the person who says: “I testify that none has the right to be worshiped except Allah (God),’ seeking thereby the Face of God.” (Saheeh Al-Bukhari)
There are many more interesting quotes out there, which you find as non inclusive to this world. For more interesting quotes out there.