What was required of him (peace and blessings be upon him) of witnessing the Truth while mixing with people in person and in speech

An angel came to the Prophet (peace and blessings be upon him) and said: "Read." He (peace and blessings be upon him) said: "I am not one who reads." He said again: "Read." I said: "I am not one who reads." He repeated that again, then he said: "Read in the name of your Lord who created; created man from a clinging clot." [Surah al-Alaq: 1-2]
Muhammad bin al-Nu'man said: Then the Messenger of Allah (peace and blessings be upon him) went back with that. Ibn Shihab said: I heard Urwah bin al-Zubayr say that Sayyidah Aishah (may Allah be pleased with her) said: The Prophet (peace and blessings be upon him) returned to Sayyidah Khadijah (may Allah be pleased with her) with his heart trembling, and he (peace and blessings be upon him) said: "Wrap me up, wrap me up." So he (peace and blessings be upon him) was wrapped up. When (the fear) left him (peace and blessings be upon him), he (peace and blessings be upon him) said to Sayyidah Khadijah (may Allah be pleased with her): "I feared for myself." Sayyidah Khadijah (may Allah be pleased with her) said: Rejoice! By Allah, Allah will never disgrace you. You speak the truth and you keep the ties of kinship. Come with us. So Sayyidah Khadijah (may Allah be pleased with her) went to Waraqah bin Nawfal, who had become a Christian; he was a blind old man who read the Gospel in Arabic. Sayyidah Khadijah (may Allah be pleased with her) said to him: O son of my uncle, listen to your nephew. Waraqah said to him (peace and blessings be upon him): What do you see? The Messenger of Allah (peace and blessings be upon him) told him what he had seen, and Waraqah bin Nawfal said: This is the Namus (the angel of revelation) whom Allah sent down to Musa (peace be upon him). Would that I were (alive) when your people drive you out! The Messenger of Allah (peace and blessings be upon him) said: "Will they drive me out?" He said: Yes. No man has ever brought the like of what you have brought except that he was treated with enmity; and if your day reaches me, I will support you with full support.

Sayyiduna Jabir bin Abdullah al-Ansari (may Allah be pleased with them both) heard the Prophet (peace and blessings be upon him) say: "Then the revelation stopped for some days. Once, while I was walking, I heard a voice from the sky. I raised my eyes towards the sky, and there was the angel who used to come to me, sitting on a chair between the sky and the earth. I was so terrified of him that I fell down to the ground. I came to my family and said to them: 'Wrap me up, wrap me up.'" So they wrapped him up, and Allah Almighty revealed these verses: "O you who are wrapped up! Arise and warn. And magnify your Lord. And purify your garments. And shun the rujz." [Surah al-Muddaththir: 1-5]
Abu Salamah said: Al-rujz means the idols. He (peace and blessings be upon him) said: "Then after that the revelation came, one after another."

The Prophet (peace and blessings be upon him) said: "If you knew what I know, you would laugh little and weep much."

Sayyiduna Abu Dharr (may Allah be pleased with him) said: The Prophet (peace and blessings be upon him) recited "Has there come upon man a period of time when he was not a thing worth mentioning?" [Surah al-Insan: 1] until he completed the surah. Then he (peace and blessings be upon him) said: "I see what you do not see and I hear what you do not hear. The sky creaks, and it has every right to creak; in every space the size of a finger in the sky there is an angel with his forehead placed in prostration. By Allah, if you knew what I know, you would laugh little and weep much, and you would not take pleasure in women on your beds; rather, you would go out into the wilderness seeking refuge with Allah." The narrator said: Would that I were a tree that was cut down; these are the words of Sayyiduna Abu Dharr (may Allah be pleased with him).

Simak bin Harb (may Allah have mercy on him) said: I said to Sayyiduna Jabir bin Samurah (may Allah be pleased with him): Did you use to sit in the gatherings of the Prophet (peace and blessings be upon him)? He said: Yes, many times. He (peace and blessings be upon him) would not get up from the place where he prayed until the sun had risen; when the sun had risen, he (peace and blessings be upon him) would get up. They (the Companions) would talk and recount stories of the Jahiliyyah, and the people, that is, the Companions (may Allah be pleased with them), would laugh, while he (peace and blessings be upon him) would only smile.

Simak bin Harb asked Sayyiduna Jabir bin Samurah (may Allah be pleased with him): Have you sat with the Prophet (peace and blessings be upon him)? He said: Yes. He (peace and blessings be upon him) would remain silent for long periods and laughed little. Sometimes the Companions (may Allah be pleased with them) would recite poetry or mention some other matter, and they would laugh, while he (peace and blessings be upon him) would only smile.

A group came to Zayd bin Thabit (may Allah be pleased with him) and said: Tell us a hadith about the character of the Prophet (peace and blessings be upon him). Zayd bin Thabit (may Allah be pleased with him) said: I was his (peace and blessings be upon him) neighbour. When revelation came down, he (peace and blessings be upon him) would send for me, and I would write down the revelation. When we spoke of this world, he (peace and blessings be upon him) would speak of it with us; when we remembered the Hereafter, he (peace and blessings be upon him) would do so too; and when we spoke of food, he (peace and blessings be upon him) would do so too. All these things we narrate to you about him (peace and blessings be upon him).