A. W. Tozer 
Five Vows of Spiritual Power [EPUB ebook] 

Some people object to taking vows, but in the Bible you will find many great men of God directed by covenants, promises, vows and pledges. The psalmist was not averse to the taking of vows: “Thy vows are upon me, O God, ” he said. “I will render my praises unto thee” (Psalm 56:12).

My counsel in this matter is that if you are really concerned about spiritual improvement—the gaining of new power, new life, new joy and new personal revival within your heart—you will do well to make certain vows and proceed to keep them. If you should fail, go down in humility and repent and start over. But always keep these vows before you. They will help harmonize your heart with the vast powers that flow out and down from the throne where Christ sits at the right hand of God.