Charles H. Spurgeon on Psalms 131:2

(first clause). If I have not restrained, or quieted, and compelled to silence, my soul. It is a Hebrew phrase of asseveration and of swearing: as if he would say, I have thoroughly imposed silence on my soul, that it should be tranquil, and should bear patiently the divinely imposed cross. Just as in the following Psalm we hear a like form of asseveration: "If I will come into the tabernacle of my house", meaning "I will not come", etc. —Solomon Gesner.