From the legacy of the Prophets (peace and blessings be upon them) is calling to Allah.

The Shaykh : One must inherit from them the calling to Allah the Mighty and Majestic, calling to Allah the Mighty and Majestic in secret and in public, in general and in specific. However, one must do so with insight. With what insight? With knowledge. One must have genuine knowledge. One should not take knowledge by nibbling at it and then say, "Who am I?" Some students of knowledge take knowledge by nibbling at it, and when they grasp a single issue, they say, "Who am I?" Then they start issuing fatwas, speaking, and making a commotion. It is well known that such a person, when he sits with the common people, is considered by them to be what? A great scholar, a learned shaykh, because the common person knows nothing. Therefore, a person must have knowledge by which he can call to Allah with insight. This is necessary. But it must be a call to truth, a call with wisdom. One should look at the guidance of the Prophet (peace and blessings be upon him) in calling creation to the truth: Was it through violence and harshness, or through gentleness and wisdom? It was through gentleness and wisdom. Listen to the saying of Allah the Mighty and Majestic: We ask Allah to soften our hearts for His remembrance and for our brothers. He called them with gentleness and kindness, despite his intense jealousy for him (peace and blessings be upon him). He was the most jealous of people. When Allah the Exalted revealed: Sa'd ibn Ubadah (may Allah be pleased with him) was among the most jealous of people. He said: Look at Sa'd's words. That is, if he finds a man with his wife: What does "not sheathing" mean? It means: I strike him with the edge, I cut him in two. So the Prophet (peace and blessings be upon him and his family) said: The point is: The Messenger (peace and blessings be upon him) was the most jealous of people, and yet in his calling to Allah, he used gentleness and ease. I will give you an example in the story of a Bedouin who entered the mosque of the Prophet (peace and blessings be upon him), moved to a corner, and sat down to urinate. He was urinating where? In the mosque of the Prophet (peace and blessings be upon him), the most noble of mosques after the Sacred Mosque. Who was present? The Messenger (peace and blessings be upon him) and the Companions. The people rebuked him, they shouted at him, but the Messenger (peace and blessings be upon him) said: Meaning: Do not stop his urination. So they left him alone in obedience to what? To the command of the Prophet (peace and blessings be upon him), while they saw that this was an abomination. So the abomination is an abomination, but how is it changed? When he finished urinating, the Prophet (peace and blessings be upon him) ordered a bucket of water to be poured on the urine. The harm was now ended. The place that had become impure with urine was now pure. We are left with treating this Bedouin man. The Prophet (peace and blessings be upon him) called him and said to him: Or as he (peace and blessings be upon him) said. The chest of the Bedouin opened up at the words of the Messenger (peace and blessings be upon him), but he was constrained from another angle. What did he say? He said: Because the Messenger (peace and blessings be upon him) treated him with what? With kindness and gentleness, so his chest opened up. And the Companions (may Allah be pleased with them) treated him with harshness, they shouted at him. So reflect! How did this word from this Bedouin reach this great magnitude? To the point that he said, "O Allah, have mercy on me and Muhammad, and do not have mercy on anyone with us." So the caller to Allah must have knowledge of the Shari'ah of Allah above all else, and he must have wisdom in how to handle matters? How to call people? And let him be patient with discomfort if he sees a person in an abomination and his shouting at him leads to his aversion. Let him be patient. What is the purpose? The purpose is to reform creation. The advising doctor is brought a patient who is all stench, all disease. He is patient with him, patient with his stench, with his disease, because he wants what? He wants to cure him. Similarly, you deal with this ignorant person according to what his ignorance requires, until you gain control of his heart. Because if you gain control of his heart, he will open up to you and his chest will expand.