Charles H. Spurgeon on Psalms 9:1

"I will praise the Lord with my whole heart, I will shew forth all thy marvellous works." The words "With my whole heart," serve at once to show the greatness of the deliverance wrought for the psalmist, and to distinguish him from the hypocrites —the coarser, who praise the Lord for his goodness merely with the lips; and the more refined, who praise him with just half their heart, while they secretly ascribe the deliverance more to themselves than to him. "All thy wonders," the marvellous tokens of thy grace. The psalmist shows by this term, he recognized them in all their greatness. Where this is done, there the Lord is also praised with the whole heart. Half-heartedness, and the depreciation of divine grace, go hand in hand. The (Heb.) is the (Heb.) instrum. The heart is the instrument of praise, the mouth only its organ. E. W. Hengstenberg.

Verse 1 (second clause). When we have received any special good thing from the Lord, it is well, according as we have opportunities, to tell others of it. When the woman who had lost one of her ten pieces of silver, found the missing portion of her money, she gathered her neighbours and her friends together, saying, "Rejoice with me, for I have found the piece which I had lost." We may do the same; we may tell friends and relations that we have received such-and-such a blessing, and that we trace it directly to the hand of God. Why have we not already done this? Is there a lurking unbelief as to whether it really came from God; or are we ashamed to own it before those who are perhaps accustomed to laugh at such things? Who knows so much of the marvellous works of God as his own people; if they be silent, how can we expect the world to see what he has done? Let us not be ashamed to glorify God, by telling what we know and feel he has done; let us watch our opportunity to bring out distinctly the fact of his acting; let us feel delighted at having an opportunity, from our own experience, of telling what must turn to his praise; and them that honour God, God will honour in turn; if we be willing to talk of his deeds, he will give us enough to talk about. P. B. Power, in 'I Wills' of the Psalms.