The psalmist is aware that humans can give glory to two possible objects. They can either praise the true God or they can praise idols. We are not surprised at the existence of these options. But we might be surprised at a different set of options which the psalmist mentions in verse 1. This second set is the options God has and he has two. He can give glory to his people or he can give glory to his own name. Yet if he gives the credit for success to his people, he would not be telling the truth because they are only his instruments. Therefore the psalmist realises that the only One who should receive glory from God is the Lord himself.
The psalmist gives reasons as to why God should give honour to himself and they are his steadfast love and faithfulness. He never changes, so he always is marked by those features. In contrast, Israel often showed that they were not marked by steadfast love and faithfulness, and therefore did not deserve glory. The psalmist here is reminding his fellow Israelites that, no matter their spiritual and other attainments, God alone should have all honour.
What about the nations? At that time they worshipped dumb idols which could not do a thing for their worshippers (vv. 2-7). Some might have looked nice, although all the idols I have seen in museums look ugly. Whatever their looks, they were totally useless. Yet the presence of those non-existent idols had an effect on those who worshipped them – they became like their idols (v. 8). In the ancient world, idols were given cruel and immoral links and their worshippers became cruel and immoral. We become like what or who we worship. If we live for the world, we will become worldly. If we live for God, we will become godly.
The psalmist exhorts the Israelites to trust in the Lord because he is their help and shield. He includes the professionals (‘the sons of Aaron who served in the temple’) in his exhortation because they too can forget to trust in God. Because the Lord remembered his people in the past, they can be assured that he will bless them in the future. That is why it is good to recall his dealings. His blessings extend to the high and the low, as long as they fear the Lord, and this blessing will be experienced by subsequent generations as long as they remain faithful to him (vv. 9-14).
The Lord is able to do this because he is the Creator of all things. He gave the earth to humans so that they could enjoy his goodness. They should be thankful to him for all his many blessings. Earthly enjoyment of such blessings will cease at death, but until then we should dedicate ourselves to praise him. Of course, the psalmist was aware that praise continues after death for those who have trusted in the Lord, but such praise is offered in heaven and not on earth (vv. 15-18)