With long life will I satisfy him - The margin here, is “length of days;” that is, days lengthened out or multiplied. The meaning is, I will give him length of days as he desires, or until he is satisfied with life; implying
(1) that it is natural to desire long life;
(2) that long life is to be regarded as a blessing (compare Proverbs 3:2, Proverbs 3:16; Exodus 20:12);
(3) that the tendency of religion is to lengthen out life; since virtue, temperance, regular industry, calmness of mind, moderation in all things, freedom from excesses in eating and in drinking - to all of which religion prompts - contribute to health, and to length of days (see Psalms 34:12-14, notes; Psalms 37:9, note; Psalms 55:23, note); and
(4) that a time will come, even under this promised blessing of length of days, when a man will be “satisfied” with living; when he will have no strong desire to live longer; when, under the infirmities of advanced years, and under his lonely feelings from the fact that his early friends have fallen, and under the influence of a bright hope of heaven, he will feel that he has had enough of life here, and that it is better to depart to another world.
And shew him my salvation - In another life, after he shall be “satisfied” with this life. The promise extends beyond the grave: “Godliness is profitable unto all things, having promise of the life that now is, and of that which is to come.” See the notes at 1 Timothy 4:8. Thus, religion blesses man in this life, and blesses him forever. In possession of this, it is a great thing to him to live long; and then it is a great thing to die - to go to be forever with God.