YHWH was viewed as a Father for pious individual Israelites too: “While the exact nuance of the term ‘Father’ remains hazy, there can be no doubt that even on the individual level the relationship between God and the Israelites was seen from a family point of view.”
An important development manifestly began to transpire in the intertestamental Wisdom literature of the Second Temple period. It appears that devout Israelite writers started to address God openly as Father (Wisdom 14:3). Geza Vermes even contends that Second Temple Judaism came to view their status of being God’s figurative children chiefly as a matter of merit, not hereditary privilege. He quotes Jubilees 1:24-25 in support of this position: “I will be their Father and they shall be my sons, and they shall be called the sons of the living God.” Vermes’ thesis commends itself in many ways. Yet, it may be difficult to sustain this suggestion in light of pre-intertestamental texts that also identify pious Israelites as children of God by merit. In any event, Scripture does point to certain godly Israelites being sons of YHWH. The sagacious writer of Sirach addresses YHWH as the Lord, Father and Master of his life (Sirach 23:1, 4) and exclaims: “O Lord, you are my father, you are my champion and my savior; do not abandon me in time of trouble, in the midst of storms and dangers” (Sirach 51:10). The author of 3 Maccabees additionally invokes God as “Father,” forthrightly utilizing the conventionalized expression of intimacy “O Father” (3 Maccabees 6:3, 8). The salient point here is that individual ancient Israelites viewed God as their Father and invoked him by conscripting paternal speech in their prayers. Furthermore, it is significant that “Father” is qualified by the appositional expressions “champion,” “savior” and “creator.” These terms explain how the ancient Israelites viewed God as Father.
 Vermes, Jesus in His Jewish Context, 35.