The Family Of Imran - 3:20
"If they dispute with you, say, "I and those who follow me have submitted ourselves to Allah."Say to those who have been given the Book and those who have not been given the Book, "Have you submitted?"If they submit, they will find the truth. If they turn away, your duty is only to announce. Allah sees the servants."
The religion (system) approved by Allah is Surrender (Islam):
The Cow/2:132
"Abraham and later Jacob advised their children: "My children! Allah has chosen this religion for you; die as Muslims."
The Family Of Imran/3:85
Whoever seeks a religion other than Islam (submission to God), it will not be accepted from him, and he will be of the losers in the Hereafter.
The Table Spread/5:3
Forbidden to you are carrion, blood, the flesh of swine and what is dedicated to none but Allah. Except that you slaughter them before they are dead, animals that have been strangled, shot, fallen, gored and eaten by beasts, and those slaughtered on sacred stones and distributed with fortune-telling arrows, yes, these are evil. The unbelievers have despaired of your religion today. Do not fear them; fear Me. Today I have perfected your religion for you, I have completed My blessing upon you, and I have chosen Islam as your religion. Whoever is in hardship because of hunger and eats without any temptation to sin, there is no sin on him. For Allah is Forgiving, Merciful.
The Family Of Imran/3:19
The only religion approved by Allah is Submission (Islam). Those who were given the Book, after the knowledge had come to them, differed only because of jealousy among themselves. Allah is swift in reckoning for those who deny the signs of Allah.
Prophet Joseph/12:40
Those whom you serve besides Him are but names invented by you and your fathers. Allah has not given them any power. The judgment belongs to Allah alone. He has commanded you to serve Him alone. This is the true religion. But most of the people do not know this.
The Ranks/61:9
He has sent His messenger with guidance and the true religion so that He may make it superior to all religions, even if those who associate partners dislike it.
The Clear Evidence/98:5
But they were asked to serve Him as monotheists whose religion belongs to Allah alone, and to observe prayer and pay the zakat. This is the true religion.
The Cow/2:138
"This is the system of Allah! Whose system is better than Allah´s? "To Him alone do we serve."
The Pilgrimage/22:78
And strive and strive hard for the sake of Allah. It is He who has chosen you. He has not made this religion, which is the way of your father Abraham, difficult and burdensome for you. It is He Who has called you Muslims (Muslims) before and now, so that the Messenger may be a witness to you and you may be a witness to the people. Observe the prayer and pay the zakat and cling to Allah; He is your Owner. How good the Owner and how good the Helper!