Why did the claims of prophets grow step by step, and does that speak against them?

No, it actually speaks for them. A liar only extends claims that win him applause, but prophets met fiercer hostility after every step and still went on, because God was guiding them and preparing them step by step for their heavy task.

Critics say the Holy Prophet Muhammad (saw) first addressed only his family, then Mecca, then Arabia and finally the whole world. That, they say, looks like a man whose ideas slowly grow, not like an office given by God. Some say the same about Hazrat Mirza Ghulam Ahmad (as), the Promised Messiah, who first declared himself the reformer of his century, later the Messiah, and finally also the one awaited by other religions.

Yet this is precisely where the proof lies. A liar lies for advantage, prestige or power. A politician whose statement is badly received quickly takes it back and says he was misunderstood. No one in his right mind makes a claim that makes him hated and then adds an even bigger one.

But that is exactly what these two did. Before his claim the Holy Prophet (saw) was one of the most respected men in Arabia, and afterwards he became one of the most hated. Still he went on. Hazrat Mirza Ghulam Ahmad (as) was also highly esteemed before, but after his first claim friends and even relatives abandoned him. Then he said that Jesus (as) was not the Son of God and had not died on the cross, and so he also drew the hostility of the church and of the Christian colonial power. Only someone obeying a higher command acts like this, whether he wins applause or hostility.

Why does the task not come all at once? A child does not become a doctor on the first day of school. He is prepared step by step for a greater load. In the same way God places heavy responsibility on His chosen ones little by little. The first revelation to the Holy Prophet (saw) was only the command to read, as the first verse above shows, and even that weighed heavily on him. God’s wisdom and mercy show in the fact that He crushes no one all at once.