[Be willing to] suffer hardship with me like a good soldier of Christ Jesus.

No soldier on active duty, gets himself involved in the affairs of civilian life, so that he can please the person who enlisted him [i.e., his commanding officer].

However, the solid foundation of God stands firm. [Note: This probably refers to the church. See I Tim. 3:15]. It is sealed with these words [i.e., certifying God's ownership and a commitment to Him]: "The Lord knows those who are His people," [See Num. 16:5], and "Everyone who confesses the name of the Lord should stop practicing wickedness." [See Isa. 36:13].