There are several signs that the energy of the Holy Spirit is beginning to be active in those who genuinely aspire for this to happen and are not just putting God to the test–for, according to the Wisdom of Solomon, “It is found by those who do not put it to the test, and manifests itself to those who do not distrust it” (cf. Wisdom 1:2). In some it appears as awe arising in the heart, in others as a tremulous sense of jubilation, in others as joy, in others as joy mingled with awe, or as a tremulousness mingled with joy, and sometimes it manifests itself as tears and awe.
For the soul is joyous at God’s visitation and mercy, but at the same time is in awe and trepidation at His presence because it is guilty of so many sins.
~St Gregory of Sinai (Philokalia, vol.4, pp.259-260)
Prayerful Life 