We’re all asked to love G-d; in fact, we’re commanded to. Yet while some are better at that mitzvah than others (just as some are more attuned to Rosh Hashanah than Passover, others find it easier studying Torah than praying, etc.), others are actually gifted at it, like the pious. The truth be told, one sure sign of piety in someone is the fact that his or her relationship to G-d is rooted in love and awe.
Here’s how Ramchal depicts the sort of love that the pious experience. They “actually desire and long for closeness to G-d” so powerfully that “even mentioning His name, speaking His praises, or fulfilling His mitzvahs is a sheer pleasure and delight” for them, much the way “someone who loves the bride of his youth, or his only child” feels whenever he mentions that person’s name.
“Someone who truly loves G-d wouldn’t stop his worship of Him for any reason in the world” (other than when acute circumstances dictate otherwise, of course). Such an individual “wouldn’t need to be convinced or persuaded to serve Him” because “his heart would … (always) drive him towards his love for G-d”. His would be the sort of “visceral love that just naturally overtakes a lover”.
As King David portrayed it in his own case, “My soul yearns for You, G-d, like the hart yearns for the rivulets. My soul thirsts for G-d — the living G-d. When will I see G-d’s face?” (Psalms 42:2-3); and, “My soul longs for, pines for G-d’s courtyards” (Psalms 84:3); as well as “My soul thirsts for You, my flesh hungers for You” (Psalms 63:2). And as Isaiah the prophet said, “The longing of the soul is for Your name and Your remembrance” (Isaiah 26:8); and, “My soul has longed for You in the night. While the spirit is still within me I will seek You” (Isaiah 26:9).
The truth be known it’s easy enough to be enamored of G-d when all is well and it’s clear He has blessed your soul and shone His face upon you. But it’s difficult loving Him, searching Him out, or yearning for Him when all is not well — or horrible.
The former sort is deemed selfish love, the bleatings of a spoiled and over-fed soul who expects only goodness and favor. “The true test of this love”, i.e. of one’s love of G-d “comes into play during troubles and sorrows”, Ramchal points out.
At those times you’d need to reiterate this truism to yourself again and again — the fact that, “Everything done by Heaven is for the good” (Berachot 60b). That’s to say that “even our sorrows and woes are for our ultimate good, though they may not seem to be”. That’s to say that while things may be painful, hurtful or tough now, in the end it will all prove to have mattered and to have been a part of the grand plan which we’re not privy to.
Now, while we lesser souls would need to repeat that to ourselves numbers of times and would need to ruminate about it in great depth, those pious individuals who are thoroughly enamored of G-d would somehow know the truth of that from the first, and live their lives accordingly.