These next two verses are about our role here in this world: in verse 15 it is the work of praise, and in verse 16 it is service for Christ. Verse 15 certainly refers to a direct praise to him in worship, in hymns, in daily praise and thanksgiving and prayer, because it is the fruit of our lips.
Adoration not just in the time of morning prayer or evening prayer but through the day. Do you pray often through the day, sometimes just for a few seconds? You cannot close your eyes, you are in the middle of various things, but you adore him and you express your love to him. You offer prayers of acclamation, that is to say, you thank him for some doctrine, or blessing, or deliverance. You commit everything you are doing to him and every potentially dangerous thing, especially. You express your joy and your trust, your anticipation of future blessing and glory, and you dedicate your life to him. Do you do it through the day? Has some Christian man and woman lost the art and the practice of constant prayer? At every through the day and you give thanks and keep you close to Christ. You also offer praise to God when you witness for him, when you mention the things of God and you plan and pray to find a way of speaking to some other needy person about the gospel.
Do we deprive him of his praise and thanks? No wonder the enemy of souls can put dismal thoughts into our minds and pull us down and depress us. We are vulnerable to it because we do not thank God enough. Praise him thank him. It is our eternal activity; it is the greatest source of joy. If we praise God much during the day, it will displace pride and self-love; you cannot praise God and grumble at the same time. So it will displace the rising spirit of discontent and grumbling. It will displace envy concerning what others have got, we will not be envious, jealous people. It will displace hostility to others, somebody has done something bad to us and hostility arises, but if we are regularly thanking and praising God, it displaces all those unworthy sentiments and feelings.
Why is it thus the majority of the Christian church over the centuries has gone for free composition hymns and not exclusive Psalm singing? Psalms of course, are always the basis of praise – we keenly imitate and follow the principles of the Psalms and the doctrines of the Psalms in Christian hymns. But why is it that we accept and rejoice in hymns that have been composed by men that mention Christ. Well, here is one of the texts giving the warrant for this: ‘By him [by Christ] let us offer the sacrifice of praise to God continually giving thanks to his [Christ’s] name. Similar sentiments are found in Colossians 3 and 5. We are commanded to praise Christ by name to speak of his doctrines. In the hymn of praise in Revelation 5, the vision of John concerning how the four and twenty elders (Old Testament and New Testament believers) praise God, the example of the hymn sung has nothing in it which is in the Psalter interestingly; they are all New Testament sentiments. They sing of the blood of Christ and his redemption and the future reign and the restoration of the earth under God. They sing distinctively Christian doctrines, all in the name of Christ. So these are our authority to sing of Christ; you cannot be a Christian church and not sing of Christ. The Old Testament saints now witnesses to him in the full light of gospel day. Isaac Watts and all the others were therefore quite right when they ‘Christianised’ the Psalms. They brought the name of Christ into the praise and spelled out the New Testament doctrines which in the Psalms are only spoken of in types in shadows. This is one of the texts which effectively commands us to convey all of our praise through the name of and concerning Jesus Christ and so we do.