But Jesus answered him, saying, “It is written, ‘Man shall not live by bread alone, but by every word of God.’ ” – Luke 4:4

Where can a child of God find true solace apart from that which cometh out of the mouth of the Most High? Truly, “Man doth not live by bread alone; but by every word that proceedeth out of the mouth of God doth man live;” “Thy words were found, and I did eat them;” “How sweet are thy words unto my taste! yea, sweeter than honey to my mouth!” When Nathan came to tell David of the covenant which the Lord would make with him and his house, David would scarcely have believed so great a mercy to be really his if the prophet had not began with “Thus saith the Lord.” It was not “Thus saith Nathan,” or “Thus do the ancients say,” but “Thus saith the Lord;” and David’s heart was full of holy joy when he saw the covenant to be ordered in all things and sure. When Hezekiah lay sick unto death, he turned his face to the wall and prayed; but there was no comfort to the royal suppliant until the prophet came with “Thus saith the Lord;” and when Sennacherib was about to besiege Jerusalem, and Lachish had fallen, Hezekiah prayed, and the people with him; but oh! they could not think it possible that there should be a hook put into the jaw of the mighty Assyrian, and that he should be turned back by the way in which he came, till the prophet reassured their hearts with a “Thus saith the Lord.” Zion’s sons and daughters feast upon the sure word of their faithful God. Brethren, I need not enlarge here, for I hope most of you know the preciousness of a divine promise. There is nothing wanted to stay your soul in your worst troubles, but the Word of God applied with power. God may not send you a friend; He may not raise up a deliverer; but if He shall only give you to believe His Word, that shall be enough for you. Martin Luther said: “I have covenanted with my Lord that He should not send me visions, or dreams, or even angels. I am content with this one gift of the Scriptures, which abundantly teaches and supplies all that is necessary, both for this life and that which is to come.” O Lord, only feed me on Thy Word, and I will not envy kings their delicacies, nor even the angels around Thy throne the bread of heaven on which they live. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0591.cfm

And Samuel said, Hath the LORD as great delight in burnt offerings and sacrifices, as in obeying the voice of the LORD? Behold, to obey is better than sacrifice, and to hearken than the fat of rams. – 1 Samuel 15:22

That which the Lord commands we should do-just that, and not another thing of our own devising. How very curiously people try to give God something else instead of what He asks for! The Lord says, “My son, give Me thine heart,” and they give Him ceremonies. He asks of them obedience, and they give Him will-worship. He asks faith, and love, and justice; and they offer ten thousand rivers of oil, and the fat of fed beasts. They will give all except the one thing which He will be pleased with: yet “to obey is better than sacrifice, and to hearken than the fat of rams.” If the Lord has given you true faith in Himself, you will be anxious not so much to do a notable thing as to do exactly what God would have you to do. Mind your jots and tittles with the Lord’s precepts. Attention to little things is a fine feature in obedience: it lies much more as to its essence in the little things than in the great ones. Few dare rush into great crimes, and yet they will indulge in secret rebellion, for their heart is not right with God. Hence so many mar what they call obedience by forgetting that they serve a heart-searching, rein-trying God, who observes thoughts and motives. He would have us obey Him with the heart, and that will lead us, not merely to regard a few pleasing commands, but to have respect unto all His will. Oh, for a tender conscience, which will not willfully neglect, nor presumptuously transgress! ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2195.cfm

For you were bought at a price; therefore, glorify God in your body and in your spirit, which are God’s. – 1 Corinthians 6:20

Obedience arises out of a faith which is to us the paramount principle of action. The kind of faith which produces obedience is lord of the understanding, a royal faith. The true believer believes in God beyond all his belief in anything else, and everything else. He can say, “Let God be true, but every man a liar.” His faith in God has become to him the crown of all his believings; the most assured of all his confidences. As gold is to the inferior metals, such is our trust in God to all our other trusts. To the genuine believer the eternal is as much above the temporal as the heavens are above the earth. The infinite rolls, like Noah’s flood, over the tops of the hills of the present and the finite. To the believer, let a truth be tinctured with the glory of God, and he values it; but if God and eternity be not there, he will leave these trifles to those who choose them. You must have a paramount faith in God, or else the will of God will not be a paramount rule to you. Only a reigning faith will make us subject to its power, so as to be in all things obedient to the Lord. The chief thought in life with the true believer is, “How can I obey God?” His great anxiety is to do the will of God, or acceptably to suffer that will; and if he can obey, he will make no terms with God, and stand upon no reservations. He will pray, “Refine me from the dross of rebellion, and let the furnace be as fierce as Thou wilt.” His choice is neither wealth, nor ease, nor honour; but that he may glorify God in his body, and his spirit, which are the Lord’s. Obedience has become as much his rule as self-will is the rule of others. His cry unto the Lord is, “By Thy command I stay or go. Thy will is my will; Thy pleasure is my pleasure; Thy law is my love.” ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2195.cfm