What does the Bible say about dependability?

You can depend on God's word. We have the sayings of a God who cannot lie; the promises in them are faithfully performed by Him that made them; they are all "yes and amen" in Christ.

aman, πιστός. This word in both the O.T. and the N.T. is from the same root as 'faith.' It is being true to oneself, to one's nature, to any promise given, and to any trust committed. It is in various connections often applied to God Himself. Deut. 7:9; Isa. 49:7; 1 Cor. 1:9 1 Cor. 10:13; 1 Thess. 5:24; 2 Tim. 2:13; Heb. 10:23; 1 Peter 4:19; 1 John 1:9. The Lord Jesus also is faithful. He is 'a faithful high priest' and 'a faithful and true witness.' 2 Thess. 3:3; Heb. 2:17; Rev. 1:5; Rev. 3:14; Rev. 19:11. The commandments and testimonies of God are called faithful. Ps. 119:86, 138. The words of the gospel are also faithful: the promises attached thereto will unquestionably be fulfilled. 1 Tim. 1:15; 1 Tim. 4:9; 2 Tim. 2:11; Titus 3:8; Rev. 21:5. Christians are exhorted to be faithful as stewards to any trust committed to them, and faithful as witnesses to an absent Lord. "Be thou faithful unto death, and I will give thee a crown of life." Rev. 2:10.

He is the "Amen." You find in the second epistle to the Corinthians, the first chapter, how the apostle speaks of the word he preached as having that character, of yea and amen: because in Christ is yea; in Christ is never yea and nay. No uncertainty or doubtfulness was there in Christ or His word; He was always simply positive "yea" — always speaking one thing, and absolutely to be depended upon. If we have only one word, it is a blessed reality given us in God's infinite love, which we may hang our souls upon for eternity, and which will never fail us. The character of Christ should stamp itself upon. the Christian; Christ as seen in His Word should be exhibited in His people; but if, as here so sadly in Laodicea, they have not been faithful, nevertheless He abides faithful: He is the Amen, the "faithful and true Witness." The Church has been anything but that. He is just about to remove the candlestick, because they are untrue and unfaithful; but the Lord has not failed, and He therefore presents Himself as one absolutely true and trustworthy. And that, we can say, is our joy and comfort in the midst of the failure of everything in the present day. His people's shortcoming is not His own. Infidelity may seek to justify itself by the failure of Christians; and even Christians, alas, are capable, in the general wreck, of almost charging it upon Himself. But no, He abideth faithful; He cannot deny Himself. He is the "faithful and true witness."

But the new covenant depends altogether upon God’s faithfulness, and therefore is altogether to be depended upon.

The first case of which we read in the chapter is, "If a man vow a vow to Jehovah, or swear an oath to bind his soul with a bond, he shall not break his word, he shall do according to all that proceeds out of his mouth." Do we not know who this is? We know the One who never needs to recall a word: indeed, there is none other. His word stands; we can trust it without fear.

Still we must never forget that His trustworthiness does not in the least depend upon the worthiness. Or otherwise, of our trust. "If we believe not are unfaithful! yet He abides faithful: He cannot deny Himself" ([2 Tim. 2:13). It is therefore most happily true that they who are weak in faith, and consequently do not trust Him wholly, yet find Him wholly true. This is a fact calculated, above all things, to reinforce and increase our trust in the Lord.

This consideration of the faithfulness of God to His unfaithful people, should encourage us in our lives to trust the Lord Jesus every day. Despite the fact that often we are unfaithful and let Him down, He will never go back on anything that He has promised. As Israel in a coming day will come into wonderful earthly blessing, so the believer will come into heavenly blessing. This will not be because of anything that we have done, but by the grace and faithfulness of God. Praise His name. Amen.

Therefore Israel was to fully recognize that God is absolutely faithful, perfectly dependable in keeping the covenant He had made, however many generations would follow. If Israel would keep God's commandments they would find Him true to His Word in blessing them (v.9). But also, if they refused to obey, they would find Him true to His Word in repaying their wrong doing in destroying them (v.10). Therefore, it was only wisdom to fully observe God's commandments, statutes and judgments.

If one made a vow to the Lord he must pay it all at the appointed time (v.21), for negligence in this was sin. How much better not to vow at all than to make a promise and not keep it! This law should have by itself kept Israel from making questionable vows. However, the Lord Jesus, in speaking of this law, says, "But I say to you, do not swear at all" (Mt.5:33-34). Man in the flesh is proven by Old Testament history to be untrustworthy, and therefore in the New Testament we are warned against making promises or even announcing what we are going to do in the future, which includes the very near future (James 4:13-16). For even though we intend to act on our promise, we may find ourselves unable to. What a contrast is seen in God's promises, He who not only promised but "confirmed it by an oath" (Heb.6:17), for His promise and His oath are absolute: they cannot be broken.

A woman, so naturally influenced by her emotions, might not realize the implications of a vow she makes, while a man, characterized more by a cold, calculating intelligence, might be more cautious. In contrast to this, however, Israel made a rash promise when Moses proposed the law without even telling them what that law was (Ex.10:8); secondly, when he told them (Ex.24:3) and thirdly, when he wrote it and read it to them (Ex.24:4-7). All three times they promised to keep it. They had full opportunity to be aware of all that was involved in the law, so that they had no excuse for breaking it. Yet they broke their vow very soon after making it. How much better for us then that we should depend on the faithfulness of the Lord Jesus, not trusting our own reliability.