The Him in this verse is the LordJesusChrist.

Praise the Lord that His love and mercy is extended to `whosoever will` believe and receive Him. -> Our Lord is matchless. -> He is above all and in all who receive Him. Eph 4:6

To be a SonOfGod, which is to be a SonOfTheHolySpirit, is to be BornAgain as a NewSpirit being whose life issues from the HolySpirit of Christ Jesus rather than our carnal soul.

His Word in us transforms -> our thoughts -> our words -> our actions
while His HolySpirit in us empowers us to accomplish His will.