Humans can never become God because God alone is (1) inherently immortal (1 Tim. 1:17, 6:16) and (2) uncreated. God created all things (Eph. 3:9); therefore, anything created (which includes humans) is not God nor can it become God.
However, humans (specifically, Christians) can be "sharers in the divine nature" (θείας κοινωνοὶ φύσεως) when they receive the Holy Spirit, which is both the Spirit of the Father and the Spirit of the Son, and by means of the Holy Spirit, not only do the Father and Son dwell in the Christian (John 14:23), but the Christian is joined to the Lord Jesus Christ (1 Cor. 6:17), who himself is God (John 1:1 cp. 1:14; Rev. 19:13, 22:13), and thus the Christian becomes "one spirit" with God Himself and shares in the divine nature, for God is spirit (John 4:24) in nature (φύσις).
I might also share Heinrich Meyer's remarks on 2 Pet. 1:4, wherein he writes,
As opposed to the mystic “deification,” it must be remarked, with the older interpreters, that the expression φύσις conveys the thought, not so much of the substantia, as rather of the qualitas.
And thus, the thought is not so much that we are deified and our nature is substantially metamorphosed from humanity into deity, but rather, that we share in God's substantial qualities, for example, holiness (Heb. 12:10). This, again, is by virtue of the Holy Spirit indwelling us.