Life in this world, despite its deep uncertainties, carries a profound beauty and splendor meant to be enjoyed [ביאור שטיינזלץ]. The simple, daily experience of waking up to daylight and seeing the sun is a tremendous gift, reflecting the inherent goodness of life for as long as a person is able to experience it [מצודת דוד]. Describing the visual experience of daylight as sweet captures the deep connection between human senses, blending the ideas of taste and sight to illustrate just how deeply pleasant and agreeable the light truly is [אבן עזרא, רלב״ג]. Ultimately, the imagery of enjoying the light and seeing the sun reinforces the exact same concept using different words, emphasizing the pure joy of physical existence [מצודת דוד].
Beyond the physical experience of daylight, the primary approach among commentators views this imagery as a metaphor for spiritual understanding. In this sense, the light represents the wisdom of the Torah, while the sun symbolizes the absolute clarity of religious law. Fortunate are the students who dedicate themselves to study until the law becomes entirely clear to them, free of any doubts and shining as bright as the midday sun [רש״י, תורה תמימה, צאינה וראינה]. Looking even further ahead, another perspective suggests that this sweet light represents the World to Come. True happiness belongs to those who will merit witnessing that promised spiritual illumination [תורה תמימה].
Taking a more personal view, the imagery also reflects a person's spiritual growth throughout their lifetime. In nature, God mercifully allows the soft light of dawn to precede the actual sunrise, gradually preparing the eyes. If the blazing sun were to appear suddenly out of total darkness, it would cause damage. Similarly, the early light represents the Commandments and good deeds a person performs during their youth. Making a habit of these actions early on serves as a gradual preparation, sweetening and easing the service of God as one enters old age [תעלומות חכמה]. This early groundwork is the only way a person can truly be ready to receive the intense spiritual illumination represented by the sun in their later years.
Furthermore, someone who builds a foundation of Commandments from their youth is able to live a life full of joy. This contrasts sharply with someone who strays in their early years and only repents in old age; while they may correct their path, they cannot look back and find joy in their past [אלשיך]. Because of this, a person should remain consistently dedicated to doing good throughout their life, without allowing themselves to be distracted by other fleeting pleasures [אבן עזרא].