"Heart" here is a metonym for a person's thoughts or intentions. AT: "with all honest intentions" or "with sincerity" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Receiving what God has promised believers is spoken of as if it were inheriting property and wealth from a family member. (See: [[rc://en/ta/man/translate/figs-metaphor]])
The phrase "receive the penalty" means to be punished. AT: "anyone who does unrighteousness will be punished" or "God will punish anyone who does what is unrighteous"
The abstract noun "favoritism" can be expressed with the verb "favor." To favor some people is to judge them by different standards so the result is better for them than for others who do the same actions. AT: "God does not favor anyone" or "God judges everyone by the same standard" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])