If you were also to form your prayer or intercession at that time, to the greatest degree of contrariety to that temper which you were then in, it would be an excellent means of raising your heart to the greatest state of perfection.His devotional work linked above, A Serious Call to a Devout and Holy Life, is filled with such practical, good sense advice, and well worth the reader's time.
As for instance, when at any time you find in your heart motions of envy towards any person, whether on account of his riches, power, reputation, learning, or advancement, if you should immediately betake yourself at that time to your prayers, and pray to God to bless. and prosper him in that very thing which raised your envy; if you should express and repeat your petitions in the strongest terms, beseeching God to grant him all the happiness from the enjoyment of it, that can possibly be received; you would soon find it to be the best antidote in the world, to expel the venom of that poisonous passion.
This would be such a triumph over yourself, would so humble and reduce your heart into obedience and order, that the devil would even be afraid of tempting you again in the same manner, when he saw the temptation turned into so great a means of amending and reforming the state of your heart.
Again; if in any little difference, or misunderstandings that you happened to have at any time, with a relation, a neighbour, or any one else, you should then pray for them in a more extraordinary manner than you ever did before; beseeching God to give them every grace, and blessing, and happiness, you can think of; you would have taken the speediest method that can be, of reconciling all differences, and clearing up all misunderstandings. You would then think nothing too great to be forgiven; stay for no condescensions, need no mediation of a third person, but be glad to testify your love and good-will to him who had so high a place in your secret prayers.
This would be the mighty power of such Christian devotion: it would remove all peevish passions, soften your heart into the most tender condescensions, and be the best arbitrator of all differences that happened betwixt you and any of your acquaintance.
The greatest resentments amongst friends and neighbours, most often arise from poor punctilios and little mistakes in conduct. A certain sign that their friendship is merely human, not founded upon religious considerations, or supported by such a course of mutual prayer for one another as the first Christians used.
For such devotion must necessarily either destroy such tempers, or be itself destroyed by them: you cannot possibly have any ill temper, or show any unkind behaviour to a man, for whose welfare you are so much concerned, as to be his advocate with God in private.