More Bible texts about Joy and related aspects:

Psalm 94:19: “In the multitude of my thoughts within me thy comforts delight my soul.”
2 Corinthians 12:10: “Therefore I take pleasure in infirmities, in reproaches, in necessities, in persecutions, in distresses for Christ’s sake: for when I am weak, then am I strong.”
Proverbs 15:23: “A man hath joy by the answer of his mouth: and a word spoken in due season, how good is it!”
John 16:24: “Hitherto have ye asked nothing in my name: ask, and ye shall receive, that your joy may be full.

Self-Control & Handling Anger: Ellen G. White, Review & Herald, 10/31/1907

Ellen G. White, The Review and Herald, October 31, 1907:
There is a wonderful power in silence. When impatient words are spoken to you, do not retaliate. Words spoken in reply to one who is angry, usually act as a whip, lashing the temper into greater fury. But anger met by silence quickly dies away. Let the Christian bridle his tongue, firmly resolving not to speak harsh, impatient words. With the tongue bridled, he may be victorious in every trial of patience through which he is called to pass. {RH October 31, 1907, par. 9}

In his own strength man can not rule his spirit. But through Christ he may gain self-control. In his strength he may bring his thoughts and words into subjection to the will of God. The religion of Christ brings the emotions under the control of reason, and disciplines the tongue. Under its influence the hasty temper is subdued, and the heart is filled with patience and gentleness. {RH October 31, 1907, par. 10}

Hold firmly to the One who has all power in heaven and in earth. Though you so often fail to reveal patience and calmness, do not give up the struggle. Resolve again, this time more firmly, to be patient under every provocation. And never take your eyes off your divine Example. {RH October 31, 1907, par. 11}