James 1:4

² Consider it pure joy, my brothers, when you encounter trials of many kinds,

³ because you know that the testing of your faith develops perseverance.

Allow perseverance to finish its work, so that you may be mature and complete, not lacking anything.

⁵ Now if any of you lacks wisdom, he should ask God, who gives generously to all without finding fault, and it will be given to him.

⁶ But he must ask in faith, without doubting, because he who doubts is like a wave of the sea, blown and tossed by the wind.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB: Allow perseverance to finish its work, so that you may be mature and complete, not lacking anything.
KJV: But let patience have her perfect work, that ye may be perfect and entire, wanting nothing.
WEB: Let endurance have its perfect work, that you may be perfect and complete, lacking in nothing.
ASV: And let patience have [its] perfect work, that ye may be perfect and entire, lacking in nothing.
DARBY: But let endurance have [its] perfect work, that ye may be perfect and complete, lacking in nothing.
BLB: And let endurance have [its] perfect work, so that you⁺ may be perfect and complete, lacking in nothing.

ÅB: men tålmodigheten må føre til fullkommen gjerning, for at dere kan være fullkomne og hele og ikke mangle noe.
OTB: La utholdenheten ha sin fullkomne virkning, så dere kan være modne og komplette, uten å mangle noe.
B1930: men tålmodigheten må føre til fullkommen gjerning, forat I kan være fullkomne og hele og ikke mangle noget.

1 Peter 5:10
And after you have suffered for a little while, the God of all grace, who has called you to His eternal glory in Christ, will Himself restore you, secure you, strengthen you, and establish you.
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Luke 21:19
By your patient endurance you will gain your souls.
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Matthew 5:48
Be perfect, therefore, as your heavenly Father is perfect.
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2 Timothy 3:17
so that the man of God may be complete, fully equipped for every good work.
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Galatians 6:9
Let us not grow weary in well-doing, for in due time we will reap a harvest if we do not give up.
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Hebrews 13:21
equip you with every good thing to do His will. And may He accomplish in us what is pleasing in His sight through Jesus Christ, to whom be glory forever and ever. Amen.
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James 5:7–11
Be patient, then, brothers, until the Lord’s coming. See how the farmer awaits the precious fruit of the soil—how patient he is for the fall and spring rains.
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Habakkuk 2:3
For the vision awaits an appointed time; it testifies of the end and does not lie. Though it lingers, wait for it, since it will surely come and will not delay.
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