John Gill's Exposition of the Whole Bible
Psalms 104:15
And wine that maketh glad the heart of man,.... That is, by means of rain watering the earth, vines are caused to grow out of it; which produce wine, that has such a virtue in it, as to cheer the heart of man, even of a miserable, distressed, and afflicted man, as the word p is supposed to signify, Judges 9:13. Of this nature are (and therefore are compared to wine, or expressed by it) the love of God and Christ; the blessings of grace, the doctrines of the Gospel, the ordinances of it; particularly that of the Lord's supper, and even the joys of heaven.
And oil to make his face to shine: or, "to make his face shine more than oil" q; and so it continues the account of the virtue of wine, which not only cheers the heart, but makes the countenance brisk and lively, and even shine again: but, according to our version, and others, this is a distinct effect of the rain, causing olive trees to grow out of the earth, productive of oil; which being eaten, fattens, and so makes the face to shine; as it also does by anointing with it, which was much in use for that purpose in the eastern countries, as well as for cheering and refreshing; see Ruth 3:3. Pliny r says, oil purifies or clears; and particularly of oil of almonds, he says, that it makes clean, makes bodies soft, smooths the skin, procures gracefulness; and, with honey, takes spots or specks out of the face. Kimchi makes mention of another use of oil, in lighting lamps; by which the face of man is enlightened, or light is given him. So the Targum,
"to enlighten the face with oil.''
To this the grace of the Spirit is often compared in Scripture, with which both Christ and his members are said to be anointed,
Acts 10:38. This not only cheers and refreshes them, and is therefore called the oil of joy and gladness,
Psalms 45:7, but beautifies and adorns them, and even makes them fat and flourishing, and so their faces to shine; as well as causes their lamps of profession to burn clearly, and the light of their good works to shine before men to the glory of God.
And bread which strengthens man's heart: the earth being watered with rain, causes the wheat sown in it to grow up; of which bread is made for the support of man's life, and is the chief sustenance of it; and is therefore commonly called "the staff of life", and, by the prophet, "the whole stay of bread", Isaiah 3:1, by which human nature is invigorated, and the strength of man is kept up and increased; for the phrase, see Genesis 18:5. Of this nature are the provisions of God's house, which go by the same name, the word and ordinances; and especially Christ Jesus himself, the true and living bread; by which the Christian's spiritual life is supported and maintained, and he is comforted and refreshed, and strengthened for every good work.
p אנוש "mortalis", Junius Tremellius, Piscator "sorry man", Ainsworth. q משמן "prae oleo", Vatablus, Gejerus; "magis quam oleum", Piscator. r Nat. Hist. l. 23. c. 4.