K063. What did Jesus tell us to pursue in life?"

Is it nothing? Is it happiness? Is it effortless? No, no, no. It is something which He wants us to pursue with all our hearts, and it is certainly more than happiness which is effortless:
Mat 6:33 KJV  But seek ye first the kingdom of God, and his righteousness; and all these things shall be added unto you.
Luk 1:74-75 KJV  That he would grant unto us, that we being delivered out of the hand of our enemies might serve him without fear,  (75)  In holiness and righteousness before him, all the days of our life.

Hence, a meaningful life is not to pursue our own happiness, but to seek to do the will of God, which is the pursue of His kingdom, righteousness, and holiness:
Rom 6:19 KJV  I speak after the manner of men because of the infirmity of your flesh: for as ye have yielded your members servants to uncleanness and to iniquity unto iniquity; even so now yield your members servants to righteousness unto holiness.
2Co 7:1 KJV  Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.
1Th 3:13 KJV  To the end he may stablish your hearts unblameable in holiness before God, even our Father, at the coming of our Lord Jesus Christ with all his saints.
Heb 12:10-11 KJV  For they verily for a few days chastened us after their own pleasure; but he for our profit, that we might be partakers of his holiness.  (11)  Now no chastening for the present seemeth to be joyous, but grievous: nevertheless afterward it yieldeth the peaceable fruit of righteousness unto them which are exercised thereby.
Col 3:1-2 KJV  If ye then be risen with Christ, seek those things which are above, where Christ sitteth on the right hand of God.  (2)  Set your affection on things above, not on things on the earth.
1Pe 3:11-12 KJV  Let him eschew evil, and do good; let him seek peace, and ensue it.  (12)  For the eyes of the Lord are over the righteous, and his ears are open unto their prayers: but the face of the Lord is against them that do evil.

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