1912 Abdul-Baha was in San Francisco
On the way back to San Francisco He spoke to a group of young Bahá'ís who were teaching the Cause of God and were dedicated to diffusing the divine fragrances:
Thank God that the divine bounty has reached you, that the Sun of Truth is shining upon you and that the water of everlasting life has been provided for you. If a man drinks from a sweet spring, he ought to guide others to the same sweet water.
You have asked me to speak about how to teach the Cause of God. I have spoken at length on this but I repeat that the teacher himself must be detached and devoted so that his breath may affect others. Whoever has taken a step in this field has succeeded. The doors of knowledge are opened before him, his eyes become seeing and he is assisted with the breaths of the Holy Spirit. He is guided himself and becomes the cause of guidance of others. Of course, a person sings a joyous song only when he himself is delighted and rapturous. Thus when one begins to guide others and adduces proofs, then his taste becomes sweeter and his heart more joyful.
Moreover, everything is limited except the bounty of God and this bounty descends upon man through teaching the Cause of God; then divine inspiration will assist him. It is for this reason that Christ said that whenever you wish to talk do not think about it, the Holy Spirit will inspire you. If you desire eternal honor, everlasting life and heavenly exaltation, then teach the Cause. Divine confirmations shall attend you; this has been experienced. But it calls for firmness and steadfastness. Consider the disciples of Christ and observe with what firmness they arose until the Cause of God advanced. They even sacrificed their lives for this.
In the afternoon `Abdu'l-Bahá spoke at a gathering of the believers on the importance of teaching the Cause:
Every day confirmations surround some specific pursuit and every hour has a purpose decreed for it. Today, teaching the Cause of God and spreading the divine teachings are what attract heavenly assistance. It is the season of seed-sowing and of propagating the Word of God.
In the evening He spoke about the imprisonment and persecution of the Blessed Beauty and of the power and influence of the Greatest Name. ( Mahmud’s Diary)
1945 – Inauguration of the United Nations
The United Nations was formally inaugurated on 24 October 1945, near the end of World War II, at the initiative of the Allied powers following the United Nations Conference on International Organization that convened in San Francisco on 25 April 1945.
(The Universal House of Justice, Messages 1963 to 1986, p. 682)
1979 - Release of a Compilation on Inspiring the Heart (The Universal House of Justice, Messages 1963 to 1986, p. 430)
1985 – Release of the Promise of World Peace
JOYFULLY ANNOUNCE COMPLETION STATEMENT ON PEACE ADDRESSED TO PEOPLES WORLD ARRANGEMENTS BEING MADE PRESENTATION WORLD LEADERS BEGINNING 24 OCTOBER. STATEMENT BEING SENT NATIONAL SPIRITUAL ASSEMBLIES SHORTLY. OUR HEARTS FILLED GRATITUDE BAHÁ'U'LLÁH FOR UNPRECEDENTED OPPORTUNITY ENABLING HIS SERVANTS OFFER HIS HEALING MESSAGE AT THIS CRITICAL TIME FORTUNES MANKIND.
(The Universal House of Justice, Messages 1963 to 1986, p. 669)