Magnify Jehovah with me. The Psalmist shows still another fruit which would be the result of his giving thanks to God, namely, that he shall induce others by his example to the same exercise of devotion; nay more, he calls upon all the godly to unite with him in this exercise, inviting and exhorting them heartily and with one consent to extol the Lord. Let us therefore learn, from the many instances in which God may have given helps to any of his people, to abound in hope; and when each recites the personal benefits which he has received, let all be animated unitedly and in a public manner to give praise to God. We give thanks publicly to God, not only that men may be witnesses of our gratitude, but also that they may follow our example.

O magnify the Lord with me - This seems to be addressed primarily to the "humble," those referred to in the previous verse. As they could appreciate what he would say, as they could understand the nature of his feelings in view of his deliverance, he calls upon them especially to exult with him in the goodness of God. As he and they had common calamities and trials, so might they have common joys; as they were united in danger and sorrow, so it was proper that they should be united in joy and in praise. The word "magnify' means literally "to make great," and then, to make great in the view of the mind, or to regard and treat as great. The idea is, that he wished all, in circumstances similar to those in which he had been placed, to have a just sense of the greatness of God, and of his claims to love and praise. Compare Psalm 35:27; Psalm 40:17; Psalm 69:30; Psalm 70:4; Luke 1:46.
And let us exalt his name together - Let us unite in "lifting up" his name; that is, in raising it above all other things in our own estimation, and in the view of our fellow-men; in so making it known that it shall rise above every other object, that all may see and adore.

Magnify the Lord with me - גדלו ליהוה gaddelu lavhovah, "make greatness to Jehovah;" show his greatness; and let "us exalt his name," let us show how high and glorious it is.

O magnify the Lord with me,.... The psalmist invites the humble ones, who he knew would rejoice at the goodness of God to him, to join with him in ascribing greatness to the Lord, which is meant by magnifying him; for he cannot be made great by men, only declared how great he is, and that can only be done in an imperfect manner;
and let us exalt his name together: by proclaiming him to be the most High; by making mention of his glorious perfections and works, that he be exalted; and by praising him in the highest strains; or by having the high praises of him in their mouths; and there is more pleasure as well as more glory brought to God by doing this in a social way, or by a number of saints joining together in such service.

magnify the Lord--ascribe greatness to Him, an act of praise.
together--"alike" (Psalm 33:15), or, equally, without exception.

Together - Not in place, for David was now banished from the place of God's publick worship, but in affection: let our souls meet, and let our praises meet in the ears of the all - hearing God.